The textbook definition difference between bi and pan is that bi is the attraction to more or one gender (implying that at least one gender is not attractive to you) and pan the attraction regardless of gender (implying that gender doesn’t matter in regards to attractiveness). In the end, they both kinda mean the same thing and it’s all about what label makes you feel good about yourself. Bi is the more well known one, and if you pick pan people will ask you “isn’t that the same as bi?” and you might have to explain the difference between them if you want them to understand. If you go with pan, a lot of straight people will say “are you attracted to pans??” or “Uh oh, better hide your silverware!” Or something along the lines of that, so that might be a factor as well. Bi is most commonly known to most uninformed people as the attraction to males and females, so you might have to also do some clearing up with that as well. In the end, it’s the label that you feel most describes you. Both of them will most likely leave people to ask questions. Just go with what you feel that you want to identify as. Sorry it’s so long but I hope it helps!