Mandalorian is obviously very hyped up and deservedly so. Big budget + sci fi action = hit.
I liked the first couple of episodes of The Boys because it mainly revolved around actually killing and fighting the supes but the show kinda turned into a drama in season 2.
The Office is great but there are a lot of episodes to get through. The quality also dropped quite significantly after Michael/Steve Carell left after season 7.
I'd say watch The Boys first since season 2 just wrapped up, and then Mandalorian which is streaming new episodes right now and finally the Office just cos it's so long.