Realising mistakes

You can change your settings to 'confirm each move'. That way you can see whether you are making a mistake before moving the piece.

when i started to play some otb rated games where one needs to keep a scoresheet i was a mess- i would forget to record a move, i would record a move incorrectly, etc.
i had a chess coach at the time and my recording mishaps were making my lessons sub optimal as my coach would get pgn’s of incomplete games and moves that made no sense
he helped,me realize that in many of the positions where my recording became sloppy so did my grasp of the position itself
often i would find myself making a move whilst still tangled up in my head about the position
i would move something that wasnt even relevant because i was “not current” before i made a move
so we worked on a premoving/move routine
when opponent made a move i would double and triple confirm the coordinates and record the move- then i would work on my move; go through all the work in my head and, then, return my mind to,the current reality on the board- only then would i make a move and then carefully record it
it was painstaking at first but after a few games i got a lot better at this
but it also really helped with “moving too soon” in online games
since you have awareness of this issue you are already on the way to fixing it
think about your potential moves and try to come up with your opponents replies
after you “choose” a move then return your attention to the current board position (your head might be cluttered by all the variations and moves) and double check that your intended move doesnt fall into something you overlooked
only then make your move official
you will burn a lot of clock at first and you might flag in several games but it will get better quick enough
good luck