Father & Son seeking single parents with child(ren) for active holiday during autumn break

Hello, I'd like to go on vacation with my 11-year-old son during the autumn holidays. We'd love to travel together with other children and adults (especially single parents). Where to? - still completely unclear. We'd like to have a beach, but don't want to lie around the pool all day, preferring to do something. A bit of sport and adventure would be nice. We've already been sailing, climbing, and cycling (and it's still too early for skiing). No holiday home where the adults have to take care of everything, meaning either an active club holiday or an adventure holiday. Unfortunately, we're a bit late, meaning flights to further destinations are already relatively expensive. But that would also be okay. I'm looking forward to your messages. Manuel & Gabriel