Yes it is true that this app has only caused problems for many users on this site. It is not recommended to ever be installed.
The first thing you will want to do is use any supplied uninstaller provided by the app. Even then it is likely that all remnants of the app will not be removed, as it is usually difficult to remove and would prefer to forever be running on your computer. Follow up after uninstalling by using the free EtreCheck program to verify all files relating to CleanMyMac have been removed. If you need assistance with the report you can post it here using the Additional Text option when posting. It contains no personal information and only the free download is needed. The program was developed by a fellow user here on these forums for the purpose of providing a snapshot of your system and reveals the files that are constantly running on startup.
Using EtreCheck - Apple Community
The problem with the duplicate file tool is that it has removed needed System files, which has given the program the infamous name of BrickMyMac. This will leave you with the only option of having to wipe your computer.