Path finding - breadth-first search
What I learned
C# queues : the algorith explores the tile by spreading from neighbouring tiles by adding them to a queue. The process is reapeated until the starting node is found.
C# linked list/ node system : each tile keeps tracks of its neighbouring tiles and has a parent tile, and as such can be described as a sort of linked list. Once the algorithm has reached the starting tile, it loops through the linked list of parent tile to plot the path to the destination tile.