Hi, CaptJDC. I'm Robinson, and I’m happy to help you today.
It's not recommended to move the folders "Program Files", "Program Files(x86)", and "Program Data" to another drive, most programs use the C: as the default path to work properly. Changing these folders to another drive will make most of your software stop working.
The folders Desktop, Documents, Downloads, Pictures, and Videos you can move without problems.
Step 1: Create the folder on the drive D:
1-Open the File Explorer
2-Click on "This PC" and open the "Local disk D:"
3-Create the folders Desktop, Documents, Downloads, Pictures, and Videos
Step 2: Move the folders to the new location
1-Open the File Explorer
2-Right-click on the "Documents" folder and click on properties
3-Click on the "Location" tab
4-Click on "Move..." and select the "Documents" folder on drive D and click on Ok
5-You will be asked if you want to move the files to the new location, click on "Yes" to confirm
6-Repeat this procedure for the other folders
To identify which files taking more space on your drive C:, you can an app called TreeSize Free from the Microsoft Store.
https://apps.microsoft.com/store/detail/treesiz...
I hope this information helps. If you have any questions, please let me know and I'll be glad to assist you further.