Hi wonderful workshop community
We recently got our new fence installed and now starting to plan out some landscaping.

I want it install some weatherboard panels to zone off part of the fence above where the deck will eventually go, using weatherboard panels in the image below.

From what I gather, I'll need to frame up portions of the space between the posts (RED) for the panels to be fixed to (BLUE).

Would love any input from anyone, particularly to do with type of timber, screws, brackets suitable.
Thanks again all.