What do you need and how to create a subdomain?

Question

Web development

I can not understand what is needed and how to create a subdomain. Google sends instructions on how to connect it, but it's not entirely clear. Do I need to buy a separate domain? (because if you need a lot of subdomains, buying a new domain every time is not very convenient). What do you need to buy and what to connect where?)

Answer 1

where to create?
if the site is hosted there, you can usually create a bunch of subdomains there. free of course