The “registrant” of the domain is the legal owner. When you are purchasing a domain, make sure you use your own phone number, mailing address, and email address. Sometimes business owners find out later that they don’t legally own the domain and that the web design company owns it.
To purchase a domain, you simply visit an online domain name registrar, such as GoDaddy, input the name of the domain you want to buy, and pay a fee. You are free to buy any domain that hasn’t already been registered by another party or businessperson.