Why do I play terribly in-games?

This has been a big problem for me lately. I love chess a lot, I watch videos, do private lessons with coaches online, do puzzles a lot, and I always enjoy myself when I do anything or hear anything related to it. Whenever I review games, do online lessons, watch videos, or do puzzles, the things that I learn from them make sense to me. And when I do chess related things I feel like I’m a good player. But when I play an actual game, it is totally different. I usually play quite long games, but I make the obvious blunders ever. I fall for extremely basic tactics, and I always review them after, and in that moment I understand what I did wrong, but my terrible moves in game never change.

It looks like you won your last 9 games.

I guess they were unrated but they were still wins.

In rapid games, you have won 82, lost 21 and drawn 4 games in the last 90 days.

I don't see anything to complain about.

I don’t usually use chess.com for games. Those games were just for fun against my friend, who is a beginner and who I’m trying to teach some stuff to. This pretty much started after I did an otb club yesterday, where it was 15+10 and when I made a quite obvious blunder and before I did, I was still thinking a lot (I had 1 minute left at the end of the game and my opponent had 13 minutes). The problem is my moves during the games where I make obvious mistakes

Aoooooooooooooo

I think this might be due to tunnel vision. (tunnel vision is when you only look at one side of the board or focus only where you played a move.) Before you play a move, think to yourself if any tactics are available or any pieces could just take a free piece. Dont be playing blitz, btw. Play at least 10 min games

What i just said.

I used to teach chess at various clubs. One of my students reached 2400+ FIDE.

One thing I noticed was that when a person learns something new - and especially new strategy rather than new tactics - they start making basic mistakes, the sort of obvious error that they usually avoid. It seems to be because they haven't yet managed to incorporate the new info into their chess game, so there's a conflict between the new ideas and the old.

It isn't until they play several (or even a dozen) more games that they finally succeed in assimilating the new information into their playing style... and then they stop making silly errors and start winning more games than ever before.

My advice:

Play through it.

Improvement requires study, followed by playing several more games until your style of chess play includes the new ideas... then back for more study.

Ok sure, thanks!