This is a very complex workflow for a new user. My advice is always to begin with the basics before you tackle a full workflow… then use this as your ‘rite of passage’ to truly enter the world of Dynamo.
Still I offer some pointers:
Shared parameters can be added in a workflow similar to this: https://youtu.be/8mRXo37veao
Adding them to multiple files is far more challenging however… it requires a lot of excel data processing and use of the Orchid package. Check out this post where I showed a user how to open families in the background for parameter adjustment: Creating Family Types in Revit
I recommend as a new user however you focus on some fundamentals first;
- Get/set element parameters
- Family instance vs. type to Dynamo elements
- Process excel tables
- Manage lists, sublists and transpose/mapping data
The Dynamo primer has some great starting points for all of these.
Don’t rush!