To help protect your PC and keep it running smoothly, Microsoft recommends only installing apps from the Microsoft Store. You can choose where you can get apps from and if you want to see app recommendations when you try to install an app from outside of the Microsoft Store.
Select Start > Settings > Apps > Apps & features .
Next to Choose where to get apps, select one of the available options. To see recommendations, select Anywhere, but let me know if there's a comparable app in the Microsoft Store. To stop seeing app recommendations, select Anywhere.
Note: You can also be warned if you are about to install a non-Microsoft Store app without receiving a recommendation by selecting Anywhere, but warn me before installing an app that's not from the Microsoft Store, or restrict yourself only to apps from the Microsoft Store by selecting The Microsoft Store only (Recommended).
Select Start > Settings > Apps > Apps & features.
Under Installing apps, select one of the available options. To stop seeing app recommendations, select either Allow apps from anywhere or Turn off app recommendations (options vary by Windows version).