Where should i be learning Opening Theory?

What website and or resources do you guys use to learn Theory?

Nowhere.
Just play and analyse your lost games.
'just forget about the openings and spend all that time on the endings' - Capablanca

If anything, YouTube I suppose, some channels are more entertainment than theory though.
Review your own games though. Also, even if you haven't subscribed, Chess.com lets you run it's analysis on one of your games each day for free.

anyone you'd recommend? i do go through all my games after i play them and look at the top engine moves and recommendations and use the free game review every day i play

As a player rated 1200, you are better off spending time on general positional principles and on endgames than trying to memorize long sequences of opening moves.

play OTB at a club and in tournaments. If you want to learn openings, go over your OTB games. Yes, you will be making mistakes in the opening, but you will learn from them much more quickly than if you had tried to memorize lines beforehand.

Might make sense for Capablanca but a lot my games if I'm losing in the early or middle game i bring it back fairly consistently in the end game and if I'm winning a lot of opponents just resign when they're in a losing position which i try not to do because there's always a chance they will make a mistake or you can regain the advantage by making better moves, not always obviously but its about learning not winning.

The early game is the most annoying for me and its the only guaranteed phase of the game. Im rated 2015 or something for puzzles while being 800ish elo for rapid i dunno if that's the common gap between the two or not but i find the tactics of the middle game and to some degree end game to be easier than the openings when i go against something new in the opening or decide to try something out and use the description of the first few moves chess.com gives i don't have a great understanding of what the ideas or strategy's going forward from those positions are or even how to punish mistakes in the opening or why certain moves I'm making are mistakes. the computer might flag things as not good moves, or inaccuracies or the eval bar might drop slightly. I can generally tell why the best move is the best most of the time, unless its some obscure pawn move or some or something, but sometimes I can't evaluate the position and understand why developing a knight would be better first over the bishop... unless its to do with getting a quicker castle.

I'm more searching for an understanding to why certain moves are preferably played for certain openings the thought process behind them and how to assess and punish mistakes in the openings. rather than specifically an order sequence. Im currently reading "Chess: the art of logical thinking" i'm not very far into it but i feel like an idepth analysis and talk through of the thought process behind moves during the openings would be invaluable to improving, as well as understanding why certain moves are mistakes or how to play vs certain openings and the ideas behind them.

i'm only 835 elo atm i don't think OTB tournaments are in the cards for me at the moment i am trying to get better and hope to be 1000 elo soon

I'd like to learn a bit about it preferably with some ideas and explanations behind why certain moves should be prioritised or played and the ideas behind certain openings. what mistakes to look out for how to capitalize on them etc.

I understand it's not necessary but I'd like to get a deeper understanding of these various play styles.

Well purely out of preference then I'd like to be somewhat adequate or competent in my play before I enter a "tournament". I'm also not part of a chess club

is there a reason it needs to be over the board? i'm not trying to avoid making mistakes, those mistakes can teach you a lot but sometimes at least currently i lack the understanding of why certain moves are mistakes if they aren't immediately punished, blunders, for example, are easy to learn from their immediate feedback, and you usually know you've done something you shouldn't have done, and usually you know the reason, it might not be an overnight change to fix the issue but at least the issue is easily understood.

understanding why certain move orders are preferred, the ideas and attacking concepts behind certain openings, how to punish mistakes or inaccuracies in the early game, with some positional plays or threats isn't very clear to me and neither is learning to improve on this area.

I understand that over time this will become easier for me, but i don't necessarily see this as an issue that just requires just more play time. although it certainly will require more playtime.

I'm pretty sure at least that this is something I could learn from other people's mistakes and while still making them at least, gain a deeper understanding quicker from more experienced players with years or decades of experience.

I'm looking less for just a set line of theory that i could get from going through the Engine, although i find it fascinating, at my level i doubt I'm going to come across very many people playing if any making 15 best moves in a row.

I'm looking for more of an explanation of why we're prioritizing making certain moves in openings and I guess some examples of mistakes that can be made and how to capitalize on them.

There are so many good videos on Youtube. Just search "chess opening mistakes", "punishing chess mistakes", "chess opening principles" etc. Channels like @kamrynheidi are good.

https://www.youtube.com/@kamrynheidi/videos

already subbed, i thought her video on "the London system trap" was fantastic, which explains how to massively punish a mistake commonly made at my level, i never see anyone push the C pawn vs the accelerated London system, and her most popular video on how she got to 2000 rating.

I'll search for those videos thank you!

how widely does this differ from First steps: 1 e4 e5? i imagine i should probably start with that one?

I understand it's over-emphasized but, I feel like obviously my tactics aren't amazing because im at my level but I feel like my middle game is a lot better than my early game currently

People learn more when the process is “active.” That is, the person is thinking, relating the material to what they already know, thinking of alternatives, etc. Yes, you can learn actively online, but it is easier to fall into the trap of playing passively online than OTB.

i am glad to read that you are looking at a book on basic chess thinking. There are many great books that explain a master’s thought process during a game. Adults can learn more from a few of these books than they would if they spent that time playing blitz or rapid against other beginners.

Watch the Ben Finegold video clip. Then watch it again. At your level, you should be concentrating on following general opening principles.

if you look at your losses, you will probably find that they are due to your violating basic opening principles. You don’t need a book or an engine to tell you why you fell into an opening trap, it was a violation of a general principle.

once you know those principles, you should be able to find “book” moves in an unfamiliar opening—not because you memorized a sequence of moves but because you know how to make good moves.

all this attention to learning “book” openings just slows down a player’s development.