How do I search one collection for information contained in a second collection?

I have a collection called Reviews and a collection called Users. Each Review has an ID. Users have a field called “reviewLikes,” which is populated by review IDs. I want to locate Review IDs that match any of the ID numbers in Users.reviewLikes. How in the world can I achieve this. My brain is frying right now. Thank you!

Using the aggregation framework
and in particular the $lookup stage

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