Moving through a tunnel perspective

I am still quite new to after effects. What I want to accomplish is the sense of a character

walking down a sidewalk, but not in a sideways facing fashion, I want it to be from the characters back and him walking away from the camera.

The grey is the floor while the colorful objects are things on the walls. So as the character moves forward the  objects further should be getting bigger as he is getting closer. Another thing I can't figure out is with this type of artwork once the character reaches the end thats it. I want to make it so he is walking for a long time so I would like to add more  types of colorful objects on the wall. How could I accomplish something like this?

Thanks!