Thank you RussBell for your tips. I will start playing daily chess.
How to improve

Reading a few good books is always a good idea and would likely help a lot. I would recommend several books by GM Yasser Seirawan: Play Winning Chess, Winning Chess Openings, Winning Chess Tactics, Winning Chess Strategies and Winning Chess Endings. Easy to read and covering all of the basics for beginners and intermediate players. I found them a great help and still review them from time to time. I think they would be a great help for you - for anyone.
Yes, as noted above, play slower time controls (Daily with 2 or 3 days per move). This gives you plenty of time to review your moves before making one. Always take a second look (to find an even better move). Start each game with a plan, but be ready to adjust it. Take the time to review each position, to really see how contemplated moves would help or hurt your position. Are you hanging a piece? Leaving yourself open to a fork or pin? Can you take advantage of a weak move by your opponent? These books show you how to look out for these situations and also how to set them up. Good luck.

Thank you RussBell for your tips. I will start playing daily chess.
Now THAT'S a good move! Welcome.
You say that you are bad but have a 1300+ rating?
Do as almost all sources will tell you - play longer time controls, do tactics and study.

Dear Chessfriend,
Due to this coronavirus situation, I lowered my prices. Instead of 25 EUR or 30 USD /hour, my new pupils get a discount, so the new prices are 20 EUR or 25 USD/hour. Don't hesitate to send me a message.
First of all, have you checked analysis to see what have you done wrong? (i know it is painful but consider it).
How good is your perception? For example, can you realise that your next move allowed a mate in 3 by the opponent?
Do you think before your move? Okay, i know that you will not trade your queen for a knight, but can you realise how the opponent can attack after a blunder?
I recommend you to go analyze every of your games and see when and how the analysis marks something as a "blunder". If you believe that your next move qualifies for a "blunder", then rethink it!
Maybe you need to change time controls? Look at my blitz rating, 390! (I am one of the few premium members with such a blitz rating). Blitz is not good for me! (and i will change it soon, will switch to rapid).
Whanever the case, do not give up. I know the feeling when you think you did a "brilliant !!" move and then realise that it is not brilliant, but a blunder that allows your opponent mate you in 1, or losing from an 11 year old that started playing chess 3 days ago (Yes, it has actually happened to me), but do not give up. Play with the computer, you can undo your moves. Or try puzzles.
The choice is yours.

i am so bad at chess, i keep hanging pieces left and right, and i keep losing. Can anyone help me?
Nothing but blitz, and bullet. Hmmmm...

As with most things in life. There is always someone better, and someone not as good.

Dear Chessfriend,
My discount lasts till the end of April, don’t miss it! :) Due to this coronavirus situation, I lowered my prices. :) Instead of 25 EUR or 30 USD /hour, my new pupils get a discount, so the new prices are 20 EUR or 25 USD/hour. Don't hesitate to send me a message. :)
My name is Gabor Balazs. I am a Hungarian FM, fighting for the IM title. My top ELO is 2435. I have been playing chess for 21 years. I won the Hungarian Rapid Championship twice (U16 and U18).
I love teaching chess and it is very important for me that both of us enjoy the lessons beside the hard work. I have pupils almost all the levels from beginners to advanced players (1100-2200 ELO).
Why should you choose me?
- I have a widespread opening repertoire (a lot of openings are analysed by strong Grand Masters).
- I have a lot of chess books in PDF and Chessbase format, so I can teach you the main middlegame plans, the art of calculations, famous chess games and the endgame theory.
- I have elaborated, personalized training plans, which help you to improve your skills effectively.
- I help you analyse your games deeply, so you can realise your mistakes and learn from them.
- I am really flexible and hard-working person, the quality of my work is really important for me.
Please, contact me (balazsgabor1991@gmail.com), if you are interested in working with me, I am looking forward to your message.
Play Longer Time Controls...
For many at the beginner-novice level, speed chess tends to be primarily an exercise in moving pieces around faster than your opponent while avoiding checkmate, in hopes that his/her clock runs out sooner than yours. Or being fortunate enough to be able to exploit your opponent’s blunders before they exploit yours.
There is little time to think about what you should be doing.
It makes sense that taking more time to think about what you should be doing would promote improvement in your chess skills.
An effective way to improve your chess is therefore to play mostly longer time controls, including "daily" chess, so you have time to think about what you should be doing.
This is not to suggest that you should necessarily play exclusively slow time controls or daily games, but they should be a significant percentage of your games, at least as much, if not more so than speed games which do almost nothing to promote an understanding of how to play the game well.
Here's what IM Jeremy Silman, well-known chess book author, has to say on the topic...
https://www.chess.com/article/view/longer-time-controls-are-more-instructive
And Dan Heisman, well-known chess teacher and chess book author…
https://web.archive.org/web/20140627052239/http:/www.chesscafe.com/text/heisman16.pdf
https://www.chess.com/blog/RussBell/dan-heisman-resources
and the experience of a FIDE Master...
https://www.chess.com/forum/view/general/how-blitz-and-bullet-rotted-my-brain-don-t-let-it-rot-yours
Improving Your Chess - Resources for Beginners and Beyond...
https://www.chess.com/blog/RussBell/improving-your-chess-resources-for-beginners-and-beyond
https://www.chess.com/blog/RussBell