Having both at the same time may break shit. However you can choose a distro like Debian or Arch or any one that just gives you the default DE, customize it to your liking if needed, use it for a set amount of time (like two weeks, a month, whatever) or until you feel like you have a good grasp on it and if you like it, then install another one, uninstall the previous one and repeat until you tried all the DEs you wanted to try or found the one you like and just use that one