Goldfish...
Is there really a need for you to multi-partition your drive so as to segregate your programs, personal data, etc. from the OS? For virtually every PC user there's no particular advantage in doing so and more times than not it simply complicates the organization of the system without yielding any significant advantages.
There's really no downside to organizing your single HDD/SSD by creating folders for your programs & personal data rather than multi-partitioning the drive for purposes of separating the OS from all other data.
What SHOULD be your primary concern is creating & maintaining a comprehensive backup program for your system that you will employ on a regular basis so as to backup your ENTIRE system, including your OS + all your other data. That's what's truly important for a PC user. So that in the event that your day-to-day working HDD/SSD becomes defective or completely fails or your OS becomes so hopelessly corrupted that you no longer have a bootable, functional system you will have the means at hand to restore your ENTIRE system to a bootable, functional state quickly & relatively easy. Simply multi-partitioning your drive will NOT afford you the true security you need & should have.
One of the best ways to create & maintain a comprehensive backup system covering your entire system is employing a disk-cloning program. Using the right kind of disk-cloning program will ensure this objective and provide you with peace of mind knowing that should your system go awry for one reason or another it will be a relatively simple matter to restore that system to its previous functional state.
Give this some thought.