If you can't find an app or desktop app, like Word, Excel, or other Office products, that's installed on your PC, here are a few things you can try.
If you usually start an app by tapping or clicking it from Start, but can no longer find it there, check to make sure the app wasn’t accidentally unpinned from Start.
To search for an app and pin it to Start, follow these steps:
Swipe in from the right edge of the screen, and then tap Search.(If you're using a mouse, point to the upper-right corner of the screen, move the mouse pointer down, and then click Search.)
Enter the name of the app you want to find.
If you see the app listed in the results, swipe down on or right-click the app, and then tap or click Pin to Start.
If an app you own doesn't appear in the search results, it might be installed on a different PC, but not on the one you're using.
To install an app you own from the Windows Store, follow these steps:
On the Start screen, tap or click Store to open the Windows Store.
Swipe down from the top-edge of the screen, and then tap Your apps. (If you're using a mouse, right-click, and then click Your apps.)
Swipe down on or right-click to select the apps you want to install, and then tap or click Install.
If the app doesn’t appear in the list of Your apps, it means you don’t own that app and will need to install it from the Store.
If you bought the app from the Store, but don't see it in Your apps, check your billing history to make sure that the payment was processed. Apps installed before a payment is completely processed might work for a short period of time and then stop working. For more info about how to view your billing history, see Edit payment method for the Windows Store and view billing history.