You can find and change your Aspect Ratio settings by doing the following:
1. Open Gems Of War
2. Press the 'Options' button on your Xbox One controller
3. Switch from the 'General' tab to the 'Graphics' tab
4. The first option you will see is the 'Aspect Ratio' button
Selecting this will let you resize how large/small the game is on your screen. This may help if some text appears smaller by adjusting the aspect ratio to a higher setting.