Angels have the Phone Box
Correct, but XweAponX mentioned that the OP needed to find his original key. That's not necessary if it was a W8 machine as the original key is in the BIOS. The W10 installation will see that and install the proper version (Home or Pro) per that key. Also, if the machine had W10 installed and activated, you should be able to reinstall/clean install as often as you like/need, without a key, (whether it was a W7 or W8 originally), as the digital license resides on the MS servers. So, yes. the OP should be able to clean install, select "I don't have a key" if it presents itself, and the system should activate once it goes online (although some have said it takes a reboot or two). A key should not be necessary during install.