Hi there,
My name is Jocelyn, an independent advisor and a fellow Windows 10 user happy to help.
Please try the following steps for your Files, Pictures, and Documents:
Open Windows Explorer, click on View, then click on Options and Change folder and search options.
Click on the View tab and check the box that says Always show icons, never thumbnails and uncheck the box that says Display file icon on Thumbnails.
Now you should see all the icons your pictures, files, and documents.
For your Windows icons that are missing:
Please follow the suggestions on the below-mentioned article:
https://www.online-tech-tips.com/computer-tips/...
https://www.guidingtech.com/fix-windows-10-apps...
If none of these work, you can perform a system restore back to the state where everything was working.
Please refer to this link for the steps. Select Restore from a system restore point.
https://support.microsoft.com/en-ph/help/12415/...
I hope this would help. Let me know if you need anything else.
Best,
Jocelyn
Standard Disclaimer: This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it.