I don't think Pi-Hole can query DoT and DoH resolvers directly. People usually set up unbound or AdGuard's dnsproxy, configure it to forward queries to the DoT/DoH resolver and set it as Pi-Hole's upstream resolver.

You could use Blocky for this. It can do both, apply some block lists and use DoT/DoH resolvers.

Pi-hole with cloudflared or dnscrypt-proxy are what the docs recommend.