[ratatoskrt]

If I set up my own authoritative DNS servers, can I still use DNS over TLS or DNS over HTTPS?

[kdmtctl]

If you set your own authoritative DNS, you could use it only for your zones. To use DoH, etc for the whole traffic, you need a recursive server. Unbound is a recursive server with some rudimentary authoritative extensions.

[Aachen]

Sure you can run TLS/HTTPS to your own server or to localhost if you want to keep private from the intervening systems that you are querying for a certain domain