Hello, I'm Vemmy a user like you, and I am here to offer help.
Here are three solutions that might help you with the problems you are experiencing.
Reset the Microsoft Store Cache
Press Windows key + R a box will appear called Run. In the box please type wsreset.exe
Update Windows
Settings -> Windows Updates -> Check For updates
Download and install the latest updates and restart your PC.
Microsoft Store still doesn't work? This is the best solution. (my opinion)
If these options did not work for you, there is a way to download apps from Microsoft's website. You can find this by clicking the search option in the right corner, between "All Microsoft" and "Cart." When you click on search, type in the app you want to download. If you would like to browse apps, you can search for an app. This method should allow you to download apps without using Microsoft store app on your PC.
*When doing this method please make sure to run it twice to get app installer the first time to set up. Also, make sure under "Installing apps only from Microsoft Store helps protect your device." Make sure it says "Anywhere".
https://www.youtube.com/watch?v=ui8VfW1ayoA
Hope this helps!