I assume the Presidential Debates are still a go? If so, they might be the most cringe-worthy events ever witnessed. I think that whoever your candidate is, you will spend the entire night in this position.
Biden: They will pump him full of whatever go-go juice they can get into him, in order to prop him up and hope he can somewhat coherently read note cards for a couple of hours. Otherwise, anybody with half a brain knows that he's only functioning on half a brain. He's become a feeble, doddering old man, who can't string two sentences together without slurring his speech and drooling on himself. There's a threat he won't find the stage, and if he does, good chance he'll trip over something.
Trump: The first debate for the 2020 election was a total embarrassment for DJT. He came off as exactly what he was, angry and vengeful. He will be that X1,000. After everything he's been through, and is going through, he will come out in full attack mode, and I wouldn't be the least bit surprised if it looked like he wanted to go after Biden physically.
There will be no talk of policies or plans, only accusations of Biden using the Courts to prevent him from running. It's going to be ugly. Yuuuugely ugly!!! Whoever his advisers are, should be schooling him right now on the golden opportunity he has, but Trump's ego and narcissistic personality will let all that go in one ear and out the other. It will be, "Hunter is a crook, you're a crook, and Kamala sucked a lot of dick to get where she is.
There are a ton of Trump supporters who are genuinely angry right now. He will think he has to be their advocate, and should be. But he doesn't handle angry well. It's a horrible look for him. But, it's coming.