I need to move my discourse to another domain.
Ex: Righ now my discourse running under https://xyz.com but now i want to move it completely different domain like https://abc.com so please guide me how can i do it.
There is a how-to about changing the domain name.
The title suggests that you’re moving to a new server, but the text suggests you’re using the same one.
If you are moving to a new server that’s configured for the new domain, you can just upload and restore it on the new site. It will remap the hostname as part of the restore process.
Those instructions are needed only if you want to change the hostname in place on the same server.