I have just tried this for the first time but it's too easy. How do I advance to a higher level?
If you have previous experience with a language and feel that lessons are too easy, there are several ways to advance more quickly, skipping ahead by unlocking grayed out skills and lessons.
Link to the explanation:
Try taking a proficiency test to find out your actual level.
You can take a test on each checkpoint (I'm not entirely sure if this is still a feature) or you could deactivate and reactivate your account to take the placement test, or you could click on the test on your profile.
Here is a new feature I've been lucky to be chosen to test which does just what you are asking for. I find that in the French course I now do what at other times would be very difficult to translate sentences with very little thought. I've internalized the grammar etc.