my family and i are planning on going camping out their can we do a big camping group or would each one of the have to get their own site how does that work also is it first come first serve?

If you have a bigger group, then a group site would be better for you. I went during father's day weekend and had to make reservations 6 months ahead to ensure a spot. You can check for campsite availability, occupancy limits, and fees on recreation.gov -Ivan

Check for a group campground, however you can comfortably fit two or three tents per site. Either way you should check availability online as summer is their peak season

They allow 8 people per site. Most sites are reservation only, but they have a few first come first served.