I got a Zooz 800 long range USB Stick for my home assistant yellow and I am little confused do I need to install Z-Wave JS first or can I install the add on Z-Wave JS UI and just use that? Also is the add on easier to work with than the original?
Your questions are answered in the Z-Wave documentation:
Many people prefer Z-Wave JS UI, follow its documentation if you want to use it instead with HA.