What do you think I’m doing wrong? Because I’m not sure why I’m messing up this bad.
I recommend you link to the actual games - reviewers are more likely to help if they can link to a game than if they have to download sgf
In the first game it appears, according to the AI, to be a tight match which you fought from behind to be winning comfortably, only to make a massive critical mistake at turn 184. Minus 109 points!
I can see why you played where you did - the stones at K13 are perhaps about to die
I think that the AI is telling us that the bigger group of black stones F9 is also under threat, and worth much more due to the potentially-but-not-yet dead white group that it surrounds.
I’m not as skilled as you, so take this with a grain of salt. I’ve put it here to tempt others to improve on the assessment. But what it tells me is that whole board position assessment might need some work?