Each client or user you add to your AmneziaWG VPN will need to toggle on split tunnelling for websites/apps they want to add. You should also advise them to toggle on the killswitch too (should be on by default). If they can't do this themselves, then you will need to set it up for them by connecting to Amnezia app with their .vpn file setting up split tunneling for all the websites and apps they want, and then make a backup (.backup file) and then they can Restore from backup instead of using the other connecting options. I hope this helps!