Copy data from one cell to another

I have three tables

Contacts
Opportunities
Activity

The value in Opportunities[Contact] and Activity[Contact] references Contacts[ID] (text). However, they are not all on the same row in each table (sheet).

Whenever an activity happens I need to be able to copy the Activity[Type] (enum) into the Opportunities[Stage] (enum) based on the columns Contacts (ref) matching.

Can anyone help me with the formula or automation task that I would need to use to accomplish copying Activity[Type] over to Opportunities[Stage] cell whenever the Activity[Type] is updated?