Well with the version of Android it comes with, "Lollipop", running apps from the SD card isn't possible. You would need to try and see if the phone will let you upgrade it to "Marshmallow". If no, then the instructions below won't help. If yes, then it is going to depend on if the manufacturer has restricted the option on that device or not. Sadly they do that. If it is restricted on it, then the instructions won't work either. So first you need to see if you can upgrade to "Marshmallow" then try the following...
How to turn external SD card into internal storage on "Marshmallow".
NOTE: Please be sure you start with a blank SD card. It needs to be blank because when the card is converted to "Internal" storage, it will be formatted (wiped) and encoded (making the cards data only readable by that device).
1. Go to device “Settings”, then select “Storage”.
2. Select your "SD Card", then tap the “three-dot menu“ (top-right), now select “Settings” from in there.
3. Now select “Format as internal”, and then “Erase & Format”.
4. Your SD Card will now be formatted as internal storage.
5. Reboot your phone.
NOTE: If you don't reboot the phone, many things may not work correctly, so make sure you do.