Then you'll need to change the "A" records for the root domain (often @) and probably "www" to point to your IP. Alternatively, if you're just looking to link a "subdomain" to your IP like: mycomputer.mydomain.com, you can simply add a new "A" record in the DNS area of the domain. In this example, you would create a new "A" record, with the hostname of "mycomputer", type of record would be "A record", and then value would equal your own IP.
Go into the DNS area and look for a bunch of entries, and specifically see if you see two like this:
A 18.104.22.168 (should be close to this, last few numbers maybe changed)
www A 22.214.171.124 (again, this is just the www. part of your domain pointing to the same IP... both of these are pointing to DH's IP's)