A domain name is the address of your website that people either type in a web browser address bar or link to via a search engine, website or email.
You can never own a domain name, instead you pay for the registration to use it for one or more years. When the time comes to renew, you have priority over other people's applications.
If you don't have a domain name, Weblinks can register and administer one for you. You can use the Whois website to find available domain names: https://who.is/