Don't know how to update programs/applications (Windows phone)

Go to the Store app-> tap on the three horizontally-aligned dots (...) in the bottom-right corner -> Check for updates -> you can update them one by one by tapping an application and Update or update them all by tapping Update all

Note: You need a Windows phone version 8.1 and higher to check for updates in this way. Also, you can set your device to update the applications automatically:

Go to Store -> Settings -> App updates -> Set Automatically update my apps to Yes

Also, connect your mobile device to a stable Wi-Fi network before updating the application in order to avoid paying additional charges, shorten the updating time, and to ensure that the downloaded updates won't be corrupted.