If you don’t know where or how to use Langoid for learning, you can go to Missions to guide you with it. 

Click the blinking icon in menu or click Start button

You will see the list of the Missions in order. You can’t do the other missions unless you finish the present one

After clicking the mission, you will see instructions, and a short sample video on how to do it. And after completing the mission, you can click the Claim Reward button to go to the next mission.