How do I get rid of tokens and NFTs I never asked for?

Most of it never reaches you: likely spam is filtered out before the list is drawn. For whatever is left, hide it — a switch per token under Manage tokens, a switch per item under Manage NFTs, and accounts can be hidden too.

Hiding is display only, per account. Nothing is moved, burned or sent anywhere, and the item can be unhidden from the same screen.

One warning about unsolicited tokens and NFTs: some exist purely to get you to visit a site to “claim” or sell them, where you will be asked to approve something you should not. Hide them and leave them alone. Simply holding a spam item cannot hurt you; interacting with it can.