The best way to start a business like this when you don't know anything about it is to work for a similar business until you learn it.
The second best way is to buy an existing business and learn from the owner.
The worst way is to listen to advice from strangers on the internet.
I suggest that you contact the Agricultural Extension agent in your county. He or she can give you an idea as to whether there is a need for a dealer and where to see such a business in action.