Can't fly with NAV or Heading

Dear Simmer,

I have MSFS 2024. I tried to fly the A320. I can’t see the NAV to fly the route made by Simbrief. When I fly with Heading I can’t return to Nav.
Please is there some one how can help me and fix the problem?

Thanx

Henk

If you are new to flying the A320 (as it seems), I recommend reading this Beginner Guide: