New to PC is there a way I can move all my steam games to an external hard drive then do clean install? I'd hate to download everything again.
You don't have to redownload games unless you do a clean install.
If you do a clean install what you can do is copy the games to your external, do the clean install, redownload Steam, then paste the games into where it would be normally (download a small game or something if you want it to create the folder for you). Then what you do is hit "download" on one of the games you pasted, point Steam toward that folder, and it will discover files instead of downloading them.