Linux Shout shows you how to fix the apt-key is deprecated warning.

Debian 11 or Kali Linux 'apt-key is deprecated' Warning, here is the solution

Simple methods to remove the warning "Apt Key is deprecated" on Debian 10, 11,Ubuntu 20.04 or Kali Linux for adding GPG Key

Debian 11 or Kali Linux 'apt-key is deprecated' Warning, here is the solution