Hey,
Here are some answers to your questions and comments:
We do not know if the member ever completed this robot project, since they never posted again on our forum. You could send them a private message about it, though. When logged in to the forum, click on the user’s name. You will see their profile page. From there, you should see a link to send a private message.
Typically, you make a robot turn by having motors on opposite sides go in opposite direction. You can find plenty of examples and tutorials online, such as this one.
Finding the shortest part typically requires information about all the paths available. Typically this is stored as a graph (directed graph is there is one-way paths, and weighted graph if not all paths are equal in work to go through or even both combined: directed, weighted graph).
A graph of the maze could either be programmed beforehand (if the maze is known) or built by your robot (if it is unknown in advance) as it drives through it.
Once you have the graph established, you can use any shortest path solving algorithm. A typical one that would be simple to implement would be A* based shortest path finding. You may also want to read more about pathfinding in general.
A possible way to go about this would be to figure out what algorithm you wish to implement for finding the shortest path. Then, figure out how you will obtain the data required to feed the algorithm. If the maze data is unknown/needs to be gathered by the robot, you will need to also design and implement a maze-exploring algorithm that builds a map / tries to find/explore all spaces.
We hope this helps.
Sincerely,