Plaese clarify if Easeus neeeds the OS

Looking at all the requests for using it on a USB Stick, Easeus should clear the question if their software needs the Operating system to work?
If it needs the OS, make an image with it or have second Harddrive or Partiton with an addtitonal OS using Windows and Easeus Data Receovery as well by implementing multible boot, so that you can change the drive you are recovering from. If you have a second Computer install it on both and the take the defect hard drive out, make it a USB Drive and recover it this way