Do you know friend sites that give good domain for website? Good explanation about this terms?
I am not sure what you are asking. I am assuming that you are asking about domain names.
Domain names are a premium. So you usually have to buy the name. The first step in buying a domain is to decide the TLD (Top Level Domain) for the site.
TLDs are controlled by different groups. There are national TLDs and general interest TLD. Your first post appears to be in Czech. NIC.cz controls the .cz TLD.
The general use TLDs are controlled by different organizations. Some have restrictive rules. For example, they will only sell .edu domains to accredited schools. They will only sell .gov domains to government organizations and .org domains to non-profit organizations.
The site unstoppabledomains.com sells names with the tld .crypto, .zil .wallet .nft .These domains act like NFTs. They do not have have renewal fees.
There are numerous web sites called "Domain Registrars" that sell domain names. A good example is godaddy.com . Most webhosts sell domain names. So it is often best just to chose the web host and then buy the domain.