They memorize patterns thats it
How do you think in bullet.

You don't think deeply. If you see a fork, you take the fork, you see a pin, you pin it, there's little thought involved and it's more about quickly recognizing tactics, hanging pieces and weaknesses you can attack.
If you're slow at spotting tactics, you're gonna be bad at bullet which is what happens to me. I do spot tactics just not as quickly as other players at my rating range and that's why my bullet score is worse than my rapid and blitz rating

i move like this: https://www.chess.com/game/live/140858474277 aka premoving the entire game
No like genuinely, I'm tweaking. I play 10 min mode and bullet feels so weird. I can't calculate these things fast enough and doing random stuff DEFINETLY dosent help.
these people are on another astral plane, I don't know how y'all do it.