Is camping allowed? First come first serve basis? Are dogs allowed too?

Yes, camping is available year round in the park. First come first served. They allow check-in at noon. Dogs are also allowed at the campground, on-leash and always attended. However, I don't believe they are allowed on all the trails and in all the recreation areas.

Yes, yes and yes but no dogs on the trails. You can find much more at https://www.parks.ca.gov/?page_id=413