FirebaseDB - how to read/write field on treeview structure db?

I have a FirebaseDB (created with pc system) with nodes on the first level, on the second level, and on the third level

----rubber = 1234
----valve = cod345
----Handle = abcde
----glass = refAAA

Using the GetValue method and providing the CAR tag, I can read a single string containing the name of the fields and the values
How to read and write the value of the ‘valve’ field (third level node) directly?

Here is one way…


Word of warning....

Thank you very much