Should I learn openings ?

Maybe the question you should be asking is how far you could go WITH opening theory... Of course you might be able to get to 1000+ without any theory but it would be mich easier if you were able to play the first 10+ perfectly

Learning openings can be very boring I have found. You may be able to get higher rating without learning anything, although it would be much easier if you studied a handful of moves on a couple of openings. In my opinion, I think learning openings are important, but some people would rather not. Either way, you can make progress as a player. Although one way might be easier than the other. If I had to guess, without learning any openings the depending the person could possibly get around highest 1400.

Chess Openings Resources for Beginners and Beyond…
https://www.chess.com/blog/RussBell/openings-resources-for-beginners-and-beyond
https://www.chess.com/blog/RussBell

Personally, my favorite opening for beginners is the bird opening. It’s commonly played with people who don’t want to learn any openings. A couple more could be The Italian Game, The Sicilian Defense & The French Defense

Learn the Italian and the karo cahn (watch 10-minute videos of both) and then do as many puzzles as possible. Knowing and playing the same openings over and over is useful because it's hard to learn things when you see a completely new position every game. But don't spend too much of your time on it because the main thing holding people in your elo range back is literally just hanging pieces. If you stop hanging your pieces take your opponent's hanging pieces and see very basic pins, forks and such (you will develop this by playing puzzles), then you should be able to cruise to 1000.

Forget about the openings. Learn how to think during the game and openings are going to be piece of cake. I can teach you EXACTLY how to think during the game (opening, middlegame and endgame). Your chess understanding will never be the same and you will improve a lot. I charge €35/h, but if you can’t afford too many lessons, don’t worry. I can teach you a lot in an hour. Here to help if you are interested.
If you want to study by yourself, read ‘Logical Chess’. It is really instructive book. You have it on youtube as well: https://www.youtube.com/watch?v=0eTB7oHeRgM&list=PLUrgfsyInqNa1S4i8DsGJwzx1Uhn2AqlT