White to play and stop black's attack

Lol I found this

Huh

How do I avoid losing games from positions like these?

I primarily play 3|2 and fluctuate between 500-600 rating. I find myself dominating a lot of my games yet miss out on clear checkmates quite frequently. What can I do to work on this?

Why was this move brilliant?

I was playing a bot and made a brilliant move but don't understand why it's considered brilliant. Can someone please explain?

Would you have found the best move here for white?

I’m genially curious if people at my elo would find the best move here or if I’m just bad.

First brilliant in ages, had to post

Why is this a blunder? I thought it was smart since I was forcing him to either pull the rook back a pretty substantial amount or trade it (he ended up trading it, also I won in the end, also also this was probably my best game of chess yet move rating wise)

Why is taking with the Rook better... I mean I know it's a matter of degrees, but aside from them possibly moving their king what makes this not a good move (and I know, you all want me to change my font)

Be careful about bringing your Queen out early!

Weird postgame report

I know the post game report chess.com gives you is trash but this seems pretty contradictory doesn’t it?