Hypixel.net is both their website and mc server adress.
Is it just that https is on port 443 and minecraft is on port 25565?
And if that is the case, can i do something similar by making a reverse proxy have two seperate server blocks for the one domain, with different ports?
You cannot specify ports in a DNS A or AAAA record. www.example.com cannot resolve to 1.2.3.4:443 and app.domain.com cannot resolve to 1.2.3.4:5555
If the application (be it a game or whatnot) supports it, SRV records can identify a port for a hostname. So, you could have minecraft1.domain.com and an SRV record to specify port 25565, and minecraft2.domain.com SRV 25566.
This means you can have multiple Minecraft servers with the same IP address, but you won’t need to give people the port numbers to remember; the hostname allows the game to look up the port via the SRV record.
This is great for selfhosters because we generally only get one IP (until they rollout IPv6; probably half the reason they don’t)