Generating 2D collisions for maze

Hello, I am trying to make a game where the player has to navigate a maze from top down view while they can't see the rest of the maze. My problem, however, is that i can't figure out the collision on the maze. (This is my first time game making) Can anybody help my figure the collision out? i was hoping there would be a plugin that could generate the collisions based of the image but looking aroung online gave me nothing. The only other way i know of would be with polygon collider but that would take way to long and i guess it owuld be slow and inaccurate. Any help is appreciated and have a nice day :)