Go to learning.anaplan.com and click on Model trainings tile. You should be able to see Level 1 Model building Course. Click on it and get started and at the end of the course you will have to pass the exams for Level 1.
If you do not have access to Anaplan Workspace then I would recommend you get yourself registered for 90 day free trial program. Link below
Access the Anaplan platform free for 90-days.