I doubt Trump will try to hang onto power - he hasn't enjoyed Presidenting much anyway - but he won't concede. He's already said very plainly that a Biden win would be proof of a rigged electon, and his Trumptrash cult will follow that line. Trump can go back to what he does enjoy, which is rallies and fawning interviews on Fox and OAN. He will leave the White House in unimaginably bad grace and get deeper into Q-Anon along with about 40% of the population and the entire Republican Party.
As to the legal process, I doubt Trump has any concept of his jeopardy. He's got through life with apparent impunity, and since Barr came on the scene actual impunity, and he'll expect to skate on everything again because he's a winner.
I would agree he isn't going to follow the traditions of keeping his mouth shut during the following administration, but I really don't see the machinery of the federal government bending to his will once certain markers are passed. Specifically, once the chief justice swears in whomever wins. Most of the people are career political types, or career staff and who have been through the transfer of power a few times.
The idea that he will be dragged out in cuffs is political porn fantasies.
He will do what he does. File numerous court filings. But as those get shot down, he will tweet, but the idea he will be physically removed from the WH? Pure fantasy.