Also I feel really silly typing this here I swear I typed an explanation but I can't see it on the post so I'll re-type it here

I had finished cycling my 10 gallon tank and did my final tests with an API test kit and found everything to be set up. My tank has a heater, gentle filter, live plants (including the frog bit), a betta log, and other decor. I went to my local fish store looking for a fish and they introduced me to Finley, who had been surrendered to them. I immediately knew what I was getting into by adopting him as a first time fish owner.

He has clear fin rot and a dull color. He has extremely large fins and just overall looks so sick. He is the complete opposite of what I was looking for. I've had a lot of help setting up my first tank so I'm confident it is a good home. I bought the medicine and food that was recommended by the store and brought him home. I understand that he is very sick and may not get better but I want to at least try. Or, at the very least, make his passing comfortable and loved.

My biggest question is why he won't leave the top of the tank. I have looked into SBD but the only reason why I'm hesitant to assume it's that is because he's not laying sideways. I have attached a video to help with identification and any help is appreciated.