In one hosting account, you can host several different sites at once.
The new domain should be sent to the same DNS servers as the main one
ns1.s0avahost.net
ns2.s0avahost.net

And after that, you need to add the site to the hosting account (in the control panel cPanel).

You can add the domain as an Alias (a parked domain), then it will link to the main domain
(you will get one site with two addresses).

And you can add a domain as "Additional Domain" (Addon Domain), then the second domain
will have a separate website.
(it will be located in a separate directory in your account).