How do domain name companies create and sell domain names?

    The domain registrar doesn't sell you your domain name; What they sell is like some kind of rental of top level domains like .com .xyz, .org, .net. When buying a domain, you need to find the real name part yourself.
    The World Wide Web address is a placeholder, the front part is your name, which you find at your preference. In fact, domain companies do not 'create' domains; As customers of domain companies, you do this.

    Registrars are only given the right to advertise and manage new domains, they do not actually create them. What record companies do; Indicates that if the domain already exists, it cannot be used, and if the domain exists, it offers the buyer a registration fee. Besides companies search for popular and valuable areas, buy domains from other vendors, and keep them until they have an opportunity to sell  expenses with a margin that includes  profits. When they find the Eligible Customer, they sell with a certain profit.