Dunno what to do with old windows install

So when I used to use a Mac I was dualbooting macos (local) and Windows (external ssd) and now it’s been two years since I switched to a Windows laptop and I just realized that I could probably free up that old external ssd and use it. The only problem is that I’m kinda scared that I forgot something in my old windows install and that I’ll loose it (whatever it is that I don’t remember). I removed all the big things that took lots of place from the windows install and now it’s down to only 120GB.

What would you do in my situation, just delete the windows install to free up space or keep it just in case there’s something in it that I might want in the future.

I do have a 3rd option which is putting it in an old external HDD that does clicking sounds and is probably about to die.

I‘ll probably wait until I actually need the space but I feel kinda stupid keeping this unused widows install