CleanMyMac x not opening

Read John Galt's extensive commentary on this topic in his User Tip Effective defenses against malware and other threats.

Note particularly his warning in the section commencing with the text "Never install any product that claims to "clean up", "speed up", "optimize", "boost" or "accelerate" your Mac; to "wash" it, "tune" it, or to make it "shiny". Those claims are absurd."

cleanmymac is one of the worst things you can install on your Mac. it is well known to cause issues within macOS while providing no benefit. one thing it can do is removing things that macOS needs to function properly. you can do a search of these forums and will see that A LOT of issues posted here are solved by uninstalling that junkware.

as for antivirus apps, they are not needed nor recommended. as of catalina, macOS exists in a sealed volume that cannot be modified. not by anyone. and in any case, there are no known viruses in the wild that affect macOS.

there can be malware, but you can avoid unknowingly installing any of it by following the advice in this informative user tip: Effective defenses against malware and other threats - Apple Community. it's a long article but worth your time to read every word.

Completely uninstall CleanMyMac and never try to install it again. It's basically junk.

You're welcome. You should not install so called "cleaning" apps, antivirus/security apps or VPNs.

I have to run but I'm sure you will get answers to your questions.