how to make bi-directional relation - help pages not loading

how to make bi-directional relation - help pages not loading

probably my question is covered in the help section but I cannot access any of the help pages or videos... page not found.

I need to make a bidirectional relation between two field in two form: I have a "journalist" form and a "media" form.
I've added a lookup field in the journalist form that let me choose in which media the journalist is working
now I want that a field in the "media" form show me that information. I could insert another lookup field in "media" form but I would have to manually enter this information.

is it possible?
thanks