How make $graphLookup in $lookup lab?

Hi, can anybody help me to understand how to make $graphLookup query instead $lookup in $lookup lab?
I can’t get how to connect these two tables.
“Think back to the earlier lab on $lookup, can you think of a way to simplify the aggregation using $graphLookup instead”?"

@ Yurii_91907

The documentation on $graphLookup is here with examples. You should be able to work out how to make the change from there. Good luck.

@ Yurii_91907

I’m assuming here that you have not yet completed the Lectures on $graphLookup, which give a good in-depth review of how to use the operation. You may prefer to just do those first and then come back to this question.

Okay, thanks for your help.
Have a good day.