Unless there's some absolute fuckery from the Trump team (like Covid safety measures that somehow prevent Democrat leaning groups voting) or Biden totally shitting the bed (which isn't beyond him) then Biden will probably win.
There's a lot of talk about Trumps base of alt-right weirdos and assorted headbangers but less focus on mainstream conservative Republican voters. Older, middle class white voters - who the Republicans rely on in places like Florida, which is often one of the deciding states - have had a double whammy of the fucked economy hitting their savings and being disproportionately affected by Covid, which Trump has turned from a disaster into a catastrophe. That's likely to be more of a decider than what happens in the debates, unless one of the candidates does something truely spectacular during one of them.
As for what a Biden presidency will look like - I assume he'll be looking for a return to business as usual - global US economic dominance, 'free' trade that favours US corporations, perhaps a military intervention somewhere (but a Democrat military intervention: using drones to bomb the fuck out of defenceless foreigners with deepest sympathy), better relations with China in public while they fight like frenzied schoolkids in private, shoring up the global neo-liberal model which has lost its shine of late and maybe an eye catching policy like a Green New Deal which proves to be better for the corporations involved than the environment.
