Chess isn't actually connected to intelligence; chess is more about pattern recognition and chess experience than about IQ. It is a trope that chess is for "smart" people: https://tvtropes.org/pmwiki/pmwiki.php/Main/SmartPeoplePlayChess
Analysis of your own games is a crucial thing for learning. I realize that analysis with a computer is currently for premium accounts (not the default, free, one) but you need to do something to learn from your mistakes and make it less likely for you to repeat those and reinforce bad habits. I'd recommend even at least the chess.com Gold Membership if you can afford it, but even if you stay with the free account, there are still things you can do to improve which doesn't cost any money.
One of those things is learn the fundamentals well and I don't just mean how the pieces move. Basic checkmates (like King + Queen vs King checkmate, or King + Rook vs King checkmate), basic theoretical endgames (such as King + pawn vs King when won and when drawn) and even chess "opening principles" are useful for learning. I actually learned about opening principles (formally) embarrassingly late on my chess journey. I didn't actually learn them until I was already over 1500 chess.com rating. Most people internalize most of these fundamentals before 1000 rating and almost always before 1200 rating (even if they don't always follow them as closely as they should even after this rating).
Here is a Blog Post I wrote on opening principles years ago:
https://www.chess.com/blog/KeSetoKaiba/opening-principles-again
It might be a good place to start
chess is very connected to intelligence
I'm just playing to learn right now. The rating will climb once I figure things out.