@amohap2 you don’t have to clean your computer to be more ready for Docker. Containers contain everything they need when downloaded & ran, so what you have on your own computer doesn’t affect those. And if/when you are building your own containers, you are deterministic what you copy from host computer to image. Most of the time you add commands to Dockerfile (which determine how image is built) which download/install necessary tools from repo’s / directly from Internet sources.
So fear not, and worry not, no need to have huge cleanup operation before starting. Even after you have done many images of your own, you can push them to hub/external storage and make clean install to that computer, then pull those back and continue like nothing has happened.
All that is beauty of Docker. 