As explained in Get a domain name there are many registrars, there may be one around the corner of your street. And there are global players. Any decent hosting provider is member of the internet maintaining bodies and can offer multiple TLDs.

Some tips:

• Preferably you registrar is accredited by ICANN and TLD registers (like SIDN in The Netherlands). Another reseller should be transparant about accreditations
• Your registrar needs to speak your language and offer support via multiple channels
• Check what TLDs they support, at least your preferred TLD should be available
• Check their reputation by user reviews
• Verify if they offer decent security features, like DNSSEC, multi-factor authentication and WHOIS-protection.
• Check prices. There are lots of differences and first year discounts
• Check the options for moving domains to and from this registrar

This is by no means definite, but these are some good practices. Your experience may differ.

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