how much do you need to make to start writing off things?

Hi.I was wondering what you need to study or what your recommend to study to become an entrepreneur you know subjects i can study now in high school and in college and university. I actually want to own a restaurant and a nightclub
HELP?

Why do companies that are looking for investment need to pay the legal cost of the investors as well as their own? Is this fair? I seems to me that this limits any change of getting a good agreement. I am interested to know your view. Is this a general practice in countries outside UK?