I want to try other Free Operating Systems

Windows 10 is as good as it gets for Windows based OS's as if it's running good going to any other version of Windows would be a downgrade overall. i have been using Windows 10 x64 Pro since Dec 1st 2015 (i took advantage of the free upgrade and eventually clean installed it).

but anyways... about the only other choice you got is Linux variations (which are pretty much all free) and there seem to be plenty of those. linuxmint.com/ ; that seems to be the most popular Linux version for the desktop user, or close to it.

i would likely go with either the Cinnamon or Mate interface (right on their site it says Cinnamon 64bit is most popular so i would likely go with that) and is currently on v18.1 which is a LTS version (long term support). it will be patched/updated til April 2021 as that's the latest you can go before changing to a more updated version of Mint Linux which will further extend support. also, 64bit is what you want as only fairly old PC's would require 32bit. but if your running Windows 10 it's safe to assume your computer will run 64bit OS's.

hell, if you ain't totally sure you can always test run them in a virtual machine (i.e. www.virtualbox.org/ etc) first before taking the plunge and dump Windows 10 and install Linux Mint on your computer for real. basically using your current Windows 10 you can install that Linux Mint stuff in a virtual computer. so it runs Linux Mint from within Windows 10 using that VirtualBox program. so this way if you don't like it, you can simply delete the virtual machine data off of your computer and uninstall VirtualBox and it's like it was never on your computer and you can continue using Windows 10 like you currently are. because if you dump Windows 10 and install that and then don't like it, you basically got to reinstall Windows 10 from scratch and that can be time consuming. plus, you might have a bunch of random DATA on your computer you don't want deleted either etc.