how to reach 1400

Nah, I would just tell him to give up.
Nah, I enjoy chess, even losing, and I win as many games as I lose, so it´s no so bad.

Nah, I would just tell him to give up.
bruh how long have you even played chess, there are those who've played for over 30 years just for fun. I've played for over 9 myself, but over half of that just as a random casual player. Just because someone isn't improving doesn't mean they should quit if they find chess entertaining.

Give yourself time. You will naturally get better with a little studying. I recommend you do a puzzle book and do all those puzzles. I personally love "The Woodpecker Method" as it gives you a direct plan to get better. I did it for only a weak from being below 1400 after a massive decline in form and within a week of doing the Woodpecker Method, I reached 1520. Nothing special.
Of course this was probably luck because I lost 100 points after my membership expired. Nevertheless it was helpful.

You need to understand what you are doing and Think carefully about Each move you and your opponent make.
Most are content to have general and superficial ideas of this and that, and not because this is enough to play well but because their occasional opponents do not do better or are wrong later. But there are people who do take the trouble to investigate in-depth and if you want to beat them you have to work just as hard.
Analyse your own games No doubt about it, analysing your own games is the quickest way to get better at chess.

Nah, I would just tell him to give up.
Nah, I enjoy chess, even losing, and I win as many games as I lose, so it´s no so bad.
Okay, if you play for fun, than go ahread!
do you not play for fun? do you get paid?

Just realized you're a kid ... does your parents make you play? You should be having fun....if you were having fun you'd have faster progress.... when we have fun we do it with more passion, if we do it with more passion we do it better =]

If thats impressive I guess my 600 - 1700 improvement since february is ultra genius then?
If you are an adult, yes, that really is very impressive. If you're a kid or teenager, it's still very good, but there are (relatively speaking, of course) many others like you.

I chose to play by myself, a year ago. No one forced me. I do have fun, but there is a difference between playing casually and seriously. I do it a bit as a passion, but mostly because it would be fun to teach others, to have a neat title, and to play against other top players.
Having fun does not equal playing casually.

don't lose
and win every game
simple

Gambits:
EVERY Chess Gambit for White and Black | Chess Opening Tips
https://www.youtube.com/watch?v=_vh0ztdYTws

If you want like, real actual chess, then, the best thing I saw working in practice, is Nimzovich's idea of 'restrain' - you guess what your opponent wants to do (usually it's to pin your horse), you restrict her from doing so, she gets mad, blunder a lot, and you win. and of course, grab space.
openings?
White: London. watch GingerGM videos on it if you want a kingside attack. (3 videos)
Black:
against e4 - French - you attack, she's defending.
against d4 - either Budapest Gambit (you have a checkmate trick there) or Grunfeld - you attack, she's defending.

I chose to play by myself, a year ago. No one forced me. I do have fun, but there is a difference between playing casually and seriously. I do it a bit as a passion, but mostly because it would be fun to teach others, to have a neat title, and to play against other top players.
Having fun does not equal playing casually.
Most of the time, it does.
I played competitive tennis my whole life, national tournaments, couple state champs under my belt, made it to a few futures and challengers and played D1 in college in the u.s. and I can promise you 90% of the times I was on the court I was having fun and it definitely wasn't casual