Hi I just want to take my nephews and son in total are 6 that count like party? I need to make reservation??or we just can go

You could probably just show up the total number of people for a single game is over 20, not sure the exact number but pretty large groups and each game isn't more than 15min plus a 5-10min tutorial

Yeah,id guve them a heads up...justbin case ,but for the most part you can join other groups

It's probably best to make a reservation because sometimes large groups will arrive randomly.