If you're not sure what course to take next, the best thing to do is to join a learning Track. Each track provides a sequence of courses leading to mastery of a specific topic (Skill Tracks) or readiness for a career (Career Tracks).
You can access Tracks by clicking on Learn > Tracks while logged into DataCamp.
More information on Skill Tracks can be found here:
More information on Career Tracks can be found here:
If you are not sure which track to get started on take a look at this Career and Skill Track Help Article for more guidance.