ICANN is a public non-profit organization responsible for developing policy rules for all generic Top Level Domains (non-country-specific TLDs) such as .com, .net, .shop, and .biz.
When you register such a domain, you may receive an email with the subject "Confirm your email address for your domain (Important!)".
In this email, you will be asked to verify the email address used to register the domain. This way, ICANN verifies that the email address is valid. This email is legitimate, and to prevent the domain from being frozen, you must complete this process within 15 days, which means you must click on the link in a timely manner to verify the email address.
Before clicking on the link, verify that the URL starts as follows: https://icann-verification.registrar.eu It doesn't matter what comes after, as long as the base URL is as shown above, with https:// in front.
The email in question looks like this: