It seems to me that uninstalling udev removed a great deal more than just that package. Likely the first time you attempted to install it, the response was something like “udev already installed, set to manual”, which means that it was previously automatically already installed as a requirement for another package, but was set to “manual” selection by your attempt to reinstall it manually, when it was already there.

When you uninstalled it, everything that depends on it in some way was also removed.

The /var/log/apt directory will have log files showing what was actually removed.

I don’t have a computer in front of me, but it’s likely that the entire desktop was removed when you uninstalled udev.

Reinstalling udev would only install the things that udev depends on, not the things that depend on udev.

I’m not sure what the meta package for a Mint install is precisely called, but it’s likely something like mint-desktop.

A meta package is an empty package that doesn’t install anything itself, but it has a great many dependencies which automatically get installed when you install it.

Finally, rm -r and sudo rm -ror worse , sudo rm -rf are not commands you should be using with your level of experience because one misplaced space will cause you to irrevocably shoot yourself in the foot with no chance of undo.