Having a lot of trouble accessing ports 80 and 443 on my home network

[TheDreadPirate]

You should not use uPnP for port forwarding rules. You should set static rules. uPnP rules expire after a while on most routers.

UFW being disabled does not mean the firewall is disabled. UFW is a front end for iptables of nftables. When UFW is disabled, any rules created by UFW are disabled, but iptables/nftables is still running.

What MIGHT be happening is that your ISP is blocking ports 80 and 443. Some ISPs do not allow web servers on residential Internet plans. You would get around this by using a non-standard port to run the reverse proxy on and by using a DNS challenge for getting certs (which you've already done).

Change your reverse proxy to listen on a random port, preferably in the ephemeral range (49152–65535), setup port fowarding and UFW accordingly, and try again.