Just baught a domain, no idea how to start

so i opened my profile on the company’s website, I’m reading words like nameservers, records, or adding new records… I have no idea how to upload my folder to my domain.
any videos you know that talk about this?
is Cpanel for anybody to use or just to people who bought domains from the Cpanel company?
how to add HTTP to my domain so it can be certified, because my browser says it’s insecure…?
just to clarify, my project uses no profile registration or email contact, just a plain game with 2 HTML files, and uses local storage, so no backend either.