creating my first scenary

Hy.I want to make a scenary that will cover a part of my region (Paris) and to to enhance the small airport that's in the city i live and then upload it if it's looks great.And i want it to be very realistic, making the different stuff that i'll ad by myself.So do you know were i can find a good tutorial, that'll explain step by step the process if that is existing.Or telling me the softwares i have to download and what i have to read.ThanksPac