Plutonium

I have two doubts:
1.If I already have windows 10 on my pc, would it be more like reinstalling it?
2.If I do this process, the computer would have to be restarted again and it would be left with nothing? (No data or applications).
Sorry if I'm entertaining you with this, it's my first computer and I really wanted to play black ops ll again and obviously I don't want to screw it up or mess it up.

It is that before I had the same problem, before resetting it but they gave me another initiator and it worked for me, well I appreciate your help

I don't know if I have something to see but recently I had problems with my pc and I had to reset it but one of my hard drives got stuck with the bit locker and I also got out of the activation code to repair my files but I didn't have it anymore They didn't give it to me when I bought the pc, I don't know what to do

the launcher currently weighs 4 mb, it also already included the folder where the launcher was in the windows defender exceptions

))

My problem is that when I download the plutonium file when trying to open the launcher, it does not respond, that is, nothing opens, I already read several with this problem and I put the plutonium exception in Windows to defend but it does not work yet, please help me