Not a whole lot of detail to go off of but let's take a shot. I'd like to offer a 'problem-solution-fit' way of approaching building a business:

1) Research what problem you want to solve. Example: 'There is no British food available in my neighborhood'
2) Try to quantify how widespread the desire for a solution to this problem is. Example: Conduct neighborhood surveys to see how many people really want British food nearby.
3) What would it take to solve the problem? How can your specific resources (time, money, skills) be aligned in such a way in which you can create a product or service? Example: 'I am not a cook but I have the money necessary to hire someone who specializes in British cuisine'
4) Brush up on pricing strategy and how to appropriately price your product or service. Again, market research is key.
5) Get the word out about the solution to the problem (e.g promotion or marketing strategy)

Hope this helps! Always feel free to book a call with me to discuss further.