Doubts on genetic algorithm

Good afternoon group, my name is Vinicius and i course college in
Brazil, needs to make in my college a project using the genetic
algorithm, as example. We go to use a labyrinth of 100 houses (10 lines
X 10 columns), where the user will be able to locate in a house its
choice the image of a rat, in another one the image of a cheese and to
spread obstacles for the labyrinth. The idea is the rat to find the
cheese in order to choose optimum way through the genetic algorithm. My
doubt would be in relation the formation of the initial population,
what initial population would have to be used as so that I can to
initiate of it to apply the technique of the genetic algorithm? Who
would have as to help with an idea I to me to apply in my project?
Since already I thank the attention and I forgive will have something
made a mistake in my English.

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