Hi @yikes123 - Thanks for being part of GoDaddy Community! That depends on what you want to do with the subdomain. If you want the subdomain to be a CNAME that just points back to the naked domain, you can use the host as you've indicated and use @ in the "points to" field. There are other ways to make a subdomain, such as using an A Record, but it sounds like you're on the right track.
Normally you need to create an A record to set up the Subdomain
Then create a SRV record pointing to your subdomains page/folder or application port.
if you are using the Cpannel easy Forward or subdomain options, this can mess up how your DNS record is handled so be sure to turn those off before editing your DNS record.