Grrr!!!
I HATE Windows Media Player! I've just been trying to work out how to rip CDs to a USB stick. It's definitely NOT as intuitive as Ashampoo Burning Studio Free but here's what I've worked out anyway:
With regard to the CD you've ALREADY ripped, the files should have gone into the default 'Save' location, which is probably your 'Music' folder. You should be able to move the files to a different folder (such as one on your USB memory stick) via the usual Windows techniques. i.e. using Ctrl-A to select all of the files, then cutting them and pasting them into the desired folder.
If, after pressing Ctrl-A, you're not seeing 'Cut' when you right-click, it suggests to me that you've clicked on a WHITE area within the folder, rather than on a BLUE-highlighted file. You don't need to do it that way though; Ctrl-X is the 'Cut' shortcut, which I'd definitely expect to work for you. (You can then use Ctrl-V instead of 'Paste' if you want to).
HOWEVER it makes far more sense to rip the files DIRECTLY to the desired folder on your USB drive anyway. Then you won't need to move them at all. So, in future, BEFORE ripping a CD, click on 'Switch to Library' at the top right of your screen (unless, of course, you're already in 'Library' mode). Then click Rip Settings > More Options. Under 'Rip music to this location', click 'Change'. Click on the icon for your USB drive and then, if desired, on 'Make New Folder'. Once you've chosen your destination folder for the ripped files, click on 'OK' if you only want to use that destination for the current session or click on 'Apply', followed by 'OK' if you want the chosen folder to be the default location in future. Then click 'Rip CD' to send the ripped files directly to where you want them.