To pass an Academy practice test cycle you should have at least one approved issue report and one approved test case. Passing grade in an Academy practice cycle occurs only if you have an approved issue and approved test case in the test cycle. However, the pass grade will be assigned to you within 12 to 24 hours of getting your issue and the test case approved. When you receives a pass grade, then you will be able to sign up for the next practice test cycle.
After you pass one level, you can continue to the next course in the Academy. You may also begin to receive paid invitations to live customer cycles in the meantime, which you can also accept and participate in. However, don't feel pressured to do so. Declining an invitation before you feel that you're ready to participate in paid test cycles will not set you back, nor will it harm your rating or reputation in any way.