Thanks for the great videos and feedback
I think the only reason I am rated 800 is because I blunder in complex positions.
Often, there is a point in the game where the position is neutral and I don't know what to play.
At those moments I often end up blundering a piece, or a key square.
PS: Your channel is underrated, +1 sub.
First, I look at what is undefended on the board. (at the moment I felt the rook was more important than the queen for some reason.)
I see if I can somehow defend them, then I look at my opponent's threats. (This game it was a hanging pawn we fought over.)
If I can prevent those threats, I do so.
Then, I see if I can make my own threats.
I usually look at the king or a pawn.
I played Qc1 because if I traded bishops immediately, the black queen could take my f4 pawn.
I don't know much about the middle game but I am slowly learning.
Wow, this is actually not what I expected from someone at the 800 level. So either the levels of 800 rated players have gone up drastically since I played (which is unlikely), or you are not an 800 rated player! Your positional understanding is quite good, and your thought process is quite exceptional. However, in your comment, I see 2 problems that need to be addressed.
1. Your dealing in definites. In that position, if you took their bishop, the queen could not have taken on f4, as you would have just won a piece there. Double check your calculations and tell yourself that even though you may have been thorough, question your reasoning behind your moves.
For example, "If I take the bishop, the queen can take my pawn. That is not good. Wait... I won a bishop for a pawn, that's pretty good!"
2. This is the harder problem to solve, but one I can see already on the right track. It's the middle game, as you said, and more specifically, what plan to make. It's good that you actively look for the opponent's king and pawns, but as you grow as a chess player, these are not necessarily, the only things you want to look out for.
Personally, I look at space, weaknesses, and possible exchanges, as a means of finding a plan.
These videos go more in depth of the process,
Space
https://www.youtube.com/watch?v=TS1RHXQuJU0
Weaknesses (Part 1 and 2)
https://www.youtube.com/watch?v=bjM90rRih2Q
https://www.youtube.com/watch?v=tP45-xzvzOA
How to Find the Best Move in the Middlegame
https://www.youtube.com/watch?v=AmFDHhhPhsI
Mind you, the "Space" video is quite old, so the audio quality is kind of sketchy, but the information is still good today.