I want to improve but should I give up?

No, you just need to practice a lot and anticipate your opponent's next move. Getting a coach in real life helps too.

If improving is your aim, clapping opponent's cheeks should be your game! - Master oogway student

It's been 3 years and you are still stuck here?! I think you should get a good coach asap.

@1

Stay away from blitz and bullet. Play 15|10 rapid instead and use 40 seconds per move.
Always check your intended move is no blunder before you play it.
Think about your move. Consider 3 candidate moves. Calculate what can follow. Evaluate which is the best move. Do not play it. Imagine it played on the board. Check it is no blunder: does not hang any piece or pawn, does not run into checkmate. Only then play it.
That little mental discipline alone is enough to reach 1500.

You have to study chess in order to improve. My System by Nimzowitsch is a good start. The principles go far deeper and extend from the opening all the way into the endgame. Still with basic principles and basic combinatorial logic you should be able to get to 1000 elo on your own.

"Nowdays, if you're not a Grandmaster by 14, you can forget about it." - Anand

You need to work on elementary contacts, checkmates, and tactics, tactics, tactics. You are missing free pieces your opponents offer and you are giving them too many free pieces.

I agree, but we don't all have the same goal.
I, for one, aim to be a good club player without making a fool of myself.

I can hold positions against higher-ranked players such as chess coaches and have played a few IMs without the shame of getting crushed. I win, say, 2 out of 10. And that's good enough for me.

To most of my students, I give this advice (and it's almost all they need):

The biggest reason people struggle in lower-level chess is because of blunders. They make them in almost every game.

A mistake can instantly put you in a bad position, no matter how well you played earlier: if you had great opening knowledge, great positional skills, great endgame skills, whatever; a single mistake can change everything (you lose a piece or get checkmated).

So, how do you avoid blunders? Follow these two simple steps:

1. After your opponent moves, think if it's dangerous. Ask yourself, “What’s his idea?”
2. Before you make your move, think if it's safe. Ask yourself, “What attacking replies can he play?”

If you feel like getting to levels like 1600, 1800, or 2000 in chess is super hard, let's look at it in a different way. Those players you're facing make blunders in nearly every game they play. Beating them isn't so tough if you stop making big mistakes and start using their slip-ups to your advantage.

Again, it does not require you to become a chess nerd or spend all your time on chess. Just doing this one thing can boost your rating by a few hundred points right away.

Lastly, while avoiding blunders is crucial, I also share a few basic principles with my students. These principles help them figure out what to do in each part of the game - the opening, the middlegame, and the endgame. Understanding these simple principles is like having a map for your moves. When you use this knowledge along with being careful about blunders, you're not just getting better at defending. You're also learning a well-rounded approach to chess. Keep in mind, chess is not just about not making mistakes; it's about making smart and planned moves to outsmart your opponent.