I’ll start by plugging Harvard’s free courses catalog as well as Udemy
Edit: Gonna add 2 more I remembered-
Blender - I wish I had more time to learn it, but I did start the infamous “Donut Tutorial” once!
Watch Cartoons Online - Lots of good older stuff!
Does a pi hole combine with a VPN? I assume the pi hole can’t see what’s in the VPN traffic and therefore can’t block anything?
You could have the vpn daemon running on the pihole itself rather than on connected devices.