I set up CNAME, MX for personal mail through the domain settings at the registrar, those. now I can register the NS hosting server and nothing will go wrong?

Question

Network administration

Just as I understand it, the mail should not go astray? And the site should work on the hosting through the inscribed NS servers?

Answer 1

If you rewrite NS, then everything will go wrong and the new hoster will have to configure CNAME and MX in a new way.
But if you register a new hoster for domain A, without changing the domain administrator, nothing will go wrong.
sitename.ru A 255.255.255.255 (IP of the new hoster), without changing NS records.

Answer 2

After changing NS servers, everything that you wrote with the registrar will lose its meaning.
Read how dns works.

Answer 3

Will definitely fall off. And indicate the record.