Restrict WiFi on OpenWRT (for sharing)

Privacy Questions
1

I want to share my WiFi with many people. Now I already set up separate VLAN (aka guest network).

Now I need to do following only on guest network:

  • Block all 18+ crap
  • Block VPN (if not possible separately, block everything that are not connection to websites)
  • Block search between devices
  • Shape speed (10 Mb/s)

Can you help me with this?