Hi Evelyn
If you are having difficulty installing those applications, are you getting a message that you can only install Apps from the Microsoft Store?
If so, the Windows 10 on those tablets is in S Mode and you need to switch those out of S Mode, then you can install any software you need to on those tablets . . .
The problem is, you need to be online to switch out of S Mode . .
Open the Settings App
Go to Update and Security - Activation
In the Switch to Windows 10 Home or Switch to Windows 10 Pro section, select Go to the Store. (If you also see an "Upgrade your edition of Windows" section, be careful not to click the "Go to the Store" link that appears there.)
On the Switch out of S mode (or similar) page that appears in the Microsoft Store, select the Get button.
After you see a confirmation message on the page, you'll be able to install apps from outside of the Microsoft Store.