Typically, a subdirectory is described a folder under a domain, such as example.com/wordpress.
A subdomain is a way to name a division of a domain, wordpress.example.com. and usually points to a subdirectory (example.com/wordpress)
So subdomains typically point to a subdirectory, but a subdirectory does not require a subdomain to point to it as it is accessible by itself.
However, in your situation, I would use the subdomain for your wordpress. Create the subdomain via your cPanel first, then install your Wordpress to that subdomain. This makes it easier to access by using the subdomain name.
|Email:||support@WebHostingHub.com||Ticket:||Submit a Support Ticket|
|Chat:||Click To Chat Now|