Not usually, sex parties aren’t some free-for-all orgy with no limits. There are rules and etiquette to follow; you must gain consent and trust before any action happens. Many newbies stand out front for a while before nervously entering the club or house, only to sit and have a drink then leave - which is totally fine.
The point is to meet new people and have fun. If you get all tangled up in a threesome or some other fantasy then awesome, but you don’t need to feel pressured to do anything you don’t want to!