My dad's PC wouldn't shut down it would hang forever on the spinning circle.
I had him try a bunch of things but I accidentally marked the C partition as active.

This prevented the machine from booting.

I used the win10 disk and had him mark it inactive with DISKPART
however it must've shuffled the drive letters because now it booted to windows 7 on his 1TB HDD instead of win10 on his 120GB SSD

Since we've marked all the HDD and SSD as inactive and used the win10 disk to repair the boot.
Not sure what will happen next but I'm going to bed. I'll have my dad post more details if he decides to take over the thread.