To open a restaurant from scratch you need to create a vision onwhat would you like to serve on that restaurant, what type of food is in demand in the area where you intend to open the restaurant. how many restaurants are serving the same dishes.
Than you have to check the location and count the traffic in that area. Do the demographic study, analyse the competition, the cost of opening a restaurant, seek for a professional help. I suggest that you start by hiring a professional restaurant manager that will help you and lead you to the process of starting a restaurant.