Regarding the part where you mentioned vulnerabilities in software on Windows. Are there no similar cases to the ones you mentioned on Linux? I don't use Linux, so I really don't know. But the fact that something is open-source doesn't make it safer and more secure.
Fact is that Linux is 100% more secure than windows, that is why all servers and important information is kept on Linux operated systems not on windows, and all security experts recommend Linux.
Open source software is much more safe because anyone can inspect the code and propose bug while, while microsoft bug fixes are just creating more problems and only closed groups of people work on it.
Best things in the world are open source like Bitcoin code, or internet browsers we use every day, and closed source means you are hiding something from public for whatever the reason is.
One more plus for using and donating to open source you are directly supporting developers and not big tech corporations.
BitLocker will do it, but it is only available on Professional or Enterprise editions, which most people do not have. So you are left either trying to set up your own system which is likely to beyond the capabilities of many users, or not encrypting the whole disk but only encrypting your wallet files.
Bitlocker is closed source software and Microsoft with government agencies probably have backdoors for that encryption.
It's also trivial to bypass log-in in windows or access any files you want, so I won't encrypt anything important with that.
If you want to make the jump from Windows, then try out Linux Mint. It is designed to be as similar to Windows as possible to make the transition almost seamless. You can even boot it from a USB just to play around with it, or set up a dual boot so you can you always fall back on Windows if you need to.
There are some Linux OS that looks and feels even more like windows (Zorin OS) or like mac (Elementary OS), and best thing is to check website called Distrowatch to see most popular Linux OS.
One more interesting Windowsfx 11 Linux OS:
https://www.windowsfx.org/