i need help improving in over the board chess

Need more info on what are you doing for training at the moment. This will give others an idea on what to say to help giving you better advice instead of general suggestions.

Learn and apply the most important principles of chess.
Always blunder-check your moves.
Solve tactics in the right way.
Analyze your games.
Study games of strong players.
Learn how to be more psychologically resilient.
Work on your time management skills.
Get a coach if you can.

All of those right for sure, but the most important (until being at least titled as a CM) are blunder-checking, opening theory, analyzing your games, to get a coach and to manage your time in a way that you have time to think but you don't end up with too little at the end.

For opening theory you can search in an ECO or watch any GM/IM videos (like IM Levy, GM Hikaru, IM Alex Banzea, even GM Magnus) that published on YouTube about some openings. There are also the high-quality lessons here, but they're limited to one per week as a free member (if you pay, then you can access this and other.).

Also do lots of puzzles that you can find:
1. Here2. In chess books made for these or to learn chess (until 1800 they're useful too.).
3. In another site (I guess we all know but it's prohibited to advertise other chess sites).
4. The most odd but most useful in long-term one: your own games. Whenever you find a very difficult position in which you had advantage but gave it away or in which you blundered, take a pen and paper and write down the FEN before that move and the date in which you played the game (or create a .txt file in whatever device you're playing on and do the same here.) and then solve the puzzles you created two or three weeks after -of course OTB.

Basically the easiest way to improve OTB until high ELOs is to improve while playing online and then play sometimes OTB with someone else- or even yourself, if you write down the moves to review them with an engine after. But I can assure you that if you play against yourself too much you get much bored.

If you plan to become a titled player as soon as you can, start with these solid basics which will probably get you to 2000 before one and an half year from here if you're enough dedicated to chess. Results may vary. (Apart from joking, this method is enough useful to really get you to the 2000 with relative ease but with dedication.).

The three other things that @ChessMasteryOfficial said are the first obvious, and the last two ("Study games of strong players.
Learn how to be more psychologically resilient.")
are useful for sure, but whether if you'll want to do these or not will largely depend on how much time per day you're gonna play/study chess.

But these are general advices any chess coach (or student like me) can give. More specific advice will need more information about your training up until now and how focused you are, if you prefer rapid over classical, etc..

Almost forgot: three -very important!- things are:
1. Solve puzzles beyond your actual ELO! This will help you understand new, more challenging, concepts. And take your time while doing puzzles.
2. Focus on the game and sleep overnight! Focusing on the game much will gain you at least 250 ELO more than if not, and will also prevent obvious blunders. Sleeping benefits the focus capacity- you can focus more and for more time. Also, if playing online, never let distracting songs/ads play, as this obviuosly decreases focus much (play instead, if you like it, mostly songs without lyrics or techno songs. A 10-minute song I highly recommend, if you like the kind of music, is "Trauma" by N'to.).
3. Never let anyone hint you, surely because cheating is not allowed, but if you get hints while solving puzzles above your ELO by let's say 300 you don't learn that much (usually, at least) compared to if you don't get any hints. Well, you usually have a button -hint- next to "resign", "abandon", "give up" or whatever. Try to analyze it again, instead of trying each possible legal move in that position to see which one is correct, and only if you're relatively sure which move is right, play it (this is also for OTB tournaments). If you have no clue what to play, an hint: just don't blunder (this doesn't work in puzzles ). When your opponent plays his/her/its (if it is an engine) move, you may understand the position better already.

I know it is long but I hope it is worth reading and applying it (again, this is not case-specific but I recommend doing what I said. Also get a coach if you can and don't want to self-teach chess.).

Key is to play and analyse your lost games.

@finhero First tip for you is to stop doing Bullet games. This is not the way to improve. Bullet should be used when you just want to screw around and have fun only. The time controls are so fast you don't have time to see deep into a position and end up using instinct instead of using your knowledge of the game(tactics, positional, bad bishop, weak squares, etc.) As for building up your game(opening) you should roughly begin with knowing 3 openings for yourself up to move 5 or 6 of the mainline if possible. You should think about playing longer time controls(at least G/10 if not longer) so you have time to truly see the position and calculate the outcome. If you need some fine tuning with your game play analyze your games or seek out a "study partner" higher rated then you to go over things. I see you are newer member on Chess.com and would be willing to help. Send me a friend request. Hope that helps. Later.

Usually you should play Bullet games for fun, as this is not the way the improve. The right one is to think enough for each move you play (so play Rapid 10|0 or 15|10 instead) so that it's effectively what you were thinking was the best.

Then two more things other than the ones I said above (these still apply, as you must first improve tactics and endgames by practicing against the engine -for endgames- and humans at your level + puzzles -for tactics-. Don't worry about strategy until your ACPL goes below 28-25.):
1: Don't blunder. Always do the best you can, even against way lower players (never underestimate other's recognizing blunders and punishing them. One of the main mistakes I did while playing chess so far was in fact to underestimate lower-rated players.).
2: If you blunder, it's always your fault. Only by recognizing it was your mistake, not your opponents', you can improve. Remember this each time you made a blunder and recognize it immediately after -sure, mouseslips happen, but not that often; also it's your fault even if you mouseslip (if your mouse is not crazy and you don't have viruses on your PC.).

Another tip: if you feel like you tanked a lot recently, don't play a million games, losing all of them and so ELO. Don't play against humans, but rather the engine bots (better the KomodoX, not the "personality" ones.). If you want to play against humans, you can, just remember to play in "unrated" mode, so that you don't lose any ELO. And remember to adjust your rating range if most of your opponents is either too weak or too strong. They should always be about at your level or more to actually learn something useful (that last sentence applies over 1000 ELO, when you'll reach it.). I'm sure that following this tips you can improve fast and, if you are enough dedicated to chess, in 3-4 months you should reach 1200 average performance ELO (according to the Game Review.).

Side note: even when your opponents will flag you intentionally (which will happen a lot below 1100 ELO), you made a mistake (in that case, in time management.). You can blame them because they're playing dirty, BUT it's one more time your fault. You must manage your time well (don't play like in bullet if you're playing Rapid, and generally avoid premoving in slower time controls. But don't waste your time for nothing, as you may end up with less than a minute versus 4 full ones.).

Of course playing Bullet is ok, but fewer times and for fewer time than playing Rapid/Blitz 5|3, and/or puzzles. Bullet is of course chess, but you must play very fast; so you think less; so you are more likely to do mistakes; so you would be used to play like in bullet; so you tank in Rapid. Again, to improve your skills, it is recommended to always take your time, so play mostly slower time controls. Blitz 5|3 is better than playing Bullet but not that much, after all.

And take into account that, as you become better in slower time controls, you'll become better also in faster ones.