Question:
How can I signed up for free domain
All Wix sites come with a free Wix domain in the format accountname.wixsite.com/siteaddress which you can learn more about here.
That being said, if you’re looking for a custom domain that is specific to your business, you’ll need to upgrade to a Premium plan, which most yearly or multi-year Premium plans coming with a 1 Year Free Domain voucher.