What is the correct way to store a tree in MongoDB?

Question

MongoDB

Hello!
Please tell me, I am writing a React application with a structure,
how to save the user tree (structure)
if the user tree grows (5000, 10000, ...)?
I use this component
1. Save the entire structure for each user (it won’t be cumbersome)
2. Save the user ID under whom he registered and recurse to form a tree (structure) of the team
3. Or something else ...
Thanks for earlier.

Answer 1

Each element of the tree is a separate document in the collection with a link to the parent.