Hi and welcome to Thunkable!
How much time are you planning to spend on developing this game? I ask because if you are new to Thunkable, you may need to spend 10+ hours designing it. If you don’t have that much time, I would consider doing something else for this assignment.
Games that do not involve drag-and-drop are going to be much easier to make with Thunkable.
It’s not reasonable for me or anyone else here to tell you how to make a full jigsaw game. So I’d recommend getting started however you can – watching Thunkable tutorials, for example, and then come back to the forums and ask a specific question about a specific step you’re having trouble with.
See this: How to ask Great Questions v2.0