Wildcard subdomains are a useful cPanel feature that allows you to direct non-existing subdomains to a specific folder on your server. They serve as a “catch-all” location so that if a user enters a subdomain URL that has yet to be created (for example, http://nothinghere.yourdomain.com) they’ll be directed to the content you determine, rather than an error page.
To create a wildcard subdomain in cPanel, navigate to Domains -> Subdomains.

Complete the Create a Subdomain form, using an asterix (*) as the Subdomain name.

Select the parent domain and a folder to be used as the Document Root (this folder will hold the page content to which your users will be directed), then click Create to proceed.

With the subdomain created, now select Domains > Zone Editor from the cPanel menu. Click + A Record to create an A record for your wildcard subdomain (*.yourdomain.com.).

Note the additional period after your domain name. Ensure the A record points to your server’s IP address.

Click Add an A Record to complete the configuration.
That’s it for this tutorial!
We hope it helped you. If you have any feedback or questions, then please share them in the comments section below.