how to calculate path between player and "n" point?

hello, i’m working on a game where the player must escape a simple maze.

i’m making some kind of power ups for the player and i just want to let the player pickup a item that will show to the player the exit of the level; some kind of arrow that will be draw on the floor showing to the player the right path to the exit; the problem is that i don’t know how to get and/or calculate the path between the player and the exit point.

any help, tip or advice will be very useful.

thanks in advance for all the help.