I am “working” on a building project and what I want to do is to make walls (objects) solid so when I am in walk navigation mode not be able to walk through them. Any idea how can I do that?
Walk navigation mode is just an operator to change your point of view.
It is not made to support physics collisions between camera and scene objects.
You need a physic engine used by a game engine for such result.
In 2.79, you can connect some logic bricks and use Blender Game Engine.
But you can not do it directly in blender 2.8, 2.9.
You need to export your 3D scene to a game engine where it is possible.
Oh I see… Pity for Blender, this is a big minus. Thank you for your time!!!