The video below summarises problem based learning.
For more information, the paper “Problem-based learning (PBL): Getting the most out of your students – Their roles and responsibilities: AMEE Guide No. 84” discusses problem based learning in more detail:
https://www.tandfonline.com/doi/abs/10.3109/0142159X.2014.848269
The Team-Based Learning Collaborative website provides details and resources which may be of use in your teaching: