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.
JesseW - GoDaddy | Community Manager | 24/7 support available at x.co/247support | Remember to choose a solution and give kudos.