If you have a flash drive and an external disk you can boot into Rescuezilla (a disk cloning/backup/restore distribution) using the flash drive, save/backup your OS disk as an image in the external disk, and restore it as needed. After restoration, you will have your OS disk as it was at the time you saved it.

If you want to test out Linux, try running a virtual machine instead. There are a few good free software programs to do this. VirtualBox used to be a good option. It's a free and harmless way to dive into Linux.

Do a dual boot, that's what I did. If after some time you feel like the windows partition is unnecessary, delete it. If after deletion it suddenly seems to become necessary, it is always possible to reinstall windows, there are tutorials online on how to do that.

you should already have backups which will let you restore the system with everything you need. your post indicates you don't have one. what if some malware or hardware failure fucks it up or so? create a backup strategy that works for you. it will also give you the freedom to do experiments like this. best of luck.

Don't use "debloater" versions as that is a violation of the TOS and can create significant issues.

To install Windows just write it to a USB and then boot from the USB. Follow the on screen instructions from there

So I will get some flack from this I am sure but my daily drivers since about 2004 are Linux I have always had a Mac laptop up to a few years ago in that time frame and Windows work laptops.

Honestly Windows 11 has a lot of nice creature features that KDE has had for a while and with WSL I can use a lot of my Linux commands. Can tell you how many times I have used egrep for things along with having native ssh built in. Powershell is a very powerful shell language especially if you want to go down the .Net rabbit hole but that’s not usually needed

Still my main desktop is Debian stable with distrobox for apps I need more modern versions of. But it’s not hard to switch back and forth

When I first wanted to try Linux out I made a small 50gb partition for it. the logic was that this was the size of just one game and it was an entire operating system, so I wasn't losing much. As I continued to use Linux I kept expanding that partition to correspond with the priority I gave the OS.

Just buy a new SSD to install Linux on. If you decide to switch back just plug the old one in.

If you could install the linux then you can re-install the windows