...In the client, I saw the "Mining" tab. That is, I understand that the CRP token can be mined. What do have to do to do this?
Yes in early times it was literally so easy to mine Crypton (CRP), in the client there was a mining software and anybody with internet connection could mine some but now together with hall Utopia ecosystem mining also evolved to be able to secure the network properly and maintain it.
Here is how it works now in detail:
https://utopia-ecosystem.com/articles/3-1.html