lionn_heartt, like I said in chat you need to give us a lot more information about what you're trying to do. What if I asked you "How do build a vehicle"? You would ask me, "What kind of vehicle? Car, truck, motorcycle, bicycle, etc?" "How fast do you want it to go?" "What options do you want it to have?" "What color?" "What will it be used for?" You need to tell us what you expect your robot to do, how you want it to do it, how much you're willing to spend, how much time you have to do it, what you already know, what materials you have available, and so on.
And you should specify that "AGV" stands for "Automated Guided Vehicle". That is not a standard acronym and I expect very few people will know it.
Furthermore, this thread should be in the robotics section. Automotive electronics is for electrical systems in cars.
Matt