Just talk to Dell they say I can download Windows pro again that I got on this laptop that is like seven years old for free with a new working laptop on the thumb drive and download it to the new hard drive that I get for the old PC I get the hard drive for like 35 bucks!
Buy an SSD. And yes you can download windows 10 ISO directly from Microsoft and install it with a USB flash drive. It will activate automatically. Just select skip key. Because you have already activated from Dell. All Dell drivers should be in the factory build of Win 10 install
got a new SATA 1TB drive(same as orig) for $37, took a few hours talking to Dell for 2 nights (there stuff didnt work) to find out I hand to download Microsoft tools to get drive going, working great now! Still downloading a few Dell drivers, Win 11