Writing a function with 1 input and 1 output

I need help creating this function "walk" with one input and output. The input is labeled "number_of_steps" and the output is labeled "steps_made succesfully". I need my robot to take a "number_of_steps" forward before it hits a wall and return the number of steps before it hit the wall.

[Stephen23]

https://www.mathworks.com/help/matlab/ref/function.html

https://www.mathworks.com/help/matlab/matlab_prog/create-functions-in-files.html