My advice as a total noob too (who just played you), is to play slower games and do lots of puzzles. I've only improved a little, but I think what made the biggest difference was slowing everything down.
How *HARD* is it to improve in chess? What should I do?

I started playing blitz to get used to time pressure, but before that I used to mainly fight against bots and do 10 minute games. IRL I played a bit with friends and unlimited time xD..

Longer games are much better if you wish to improve. The thing is, in order to improve your chess, you have to think about positions you get on the board and make decisions accordingly. If you just blitz out moves, it is much harder to improve your game. Some people are exceptions, but most will not progress optimally that way.
Here you go, a few general tips:
https://www.chess.com/blog/nklristic/the-beginners-tale-first-steps-to-chess-improvement

You HAVE to be able to spot patterns in the position. Some people do it easier than others, but it is an acquired skill. Do lots of puzzles - but not blindly spamming the puzzles. Take note of where the pieces and pawns are, what you win through the tactic, what kind of theme it was, etc. And the themes don't have to be normal classifications - for example, I would always mentally call the kind of tactic where you move a piece with check to take their queen, the "surprise mf" theme in my head.

You HAVE to be able to spot patterns in the position. Some people do it easier than others, but it is an acquired skill. Do lots of puzzles - but not blindly spamming the puzzles. Take note of where the pieces and pawns are, what you win through the tactic, what kind of theme it was, etc. And the themes don't have to be normal classifications - for example, I would always mentally call the kind of tactic where you move a piece with check to take their queen, the "surprise mf" theme in my head.
Bc4+ would be better saving the bishop... but i know what u mean

You HAVE to be able to spot patterns in the position. Some people do it easier than others, but it is an acquired skill. Do lots of puzzles - but not blindly spamming the puzzles. Take note of where the pieces and pawns are, what you win through the tactic, what kind of theme it was, etc. And the themes don't have to be normal classifications - for example, I would always mentally call the kind of tactic where you move a piece with check to take their queen, the "surprise mf" theme in my head.
Bc4+ would be better saving the bishop... but i know what u mean
Usually in those kinds of tactics the minor piece just goes - so yeah. But I'm glad you got it.

Just reading something like Yasser Seirewan's "play winning chess" will give you a solid life-long foundation. It's a really short book too.

Longer games are much better if you wish to improve. The thing is, in order to improve your chess, you have to think about positions you get on the board and make decisions accordingly. If you just blitz out moves, it is much harder to improve your game. Some people are exceptions, but most will not progress optimally that way.
Here you go, a few general tips:
https://www.chess.com/blog/nklristic/the-beginners-tale-first-steps-to-chess-improvement
+1
I've been playing chess for around 2 years.... And I actually haven't improved at all xD... I've actually been going backwards... I know basic openings and beginner tactics, but I usually get surprised and defeated easily... Does anyone know what I should do?