Buy a second HDD
You can get a 250Gb M2 SSD for £30 so if you have a desktop buy one and install a fresh Linux Mint. I don't like dual booting on the same HDD as its a faff and adds compexity.
After reading the recent article about Recall I decided to make the change but I'll be honest it takes effort to start using the Linux install as everything is already installed and easy to use on Windows. Some days its easier to just use the Windows install and do what needs to be done. Its a journey so it'll come together eventually.
I will keep the windows install as I use it for Steam and games but am fully bought into the idea of dropping Windows for every other use case.
https://www.ebuyer.com/2481301-crucial-e100-480gb-m-2-internal-ssd-ct480e100ssd8