Web design for a garment company

Hi recently my father's friend has asked me to develop a website for his company. I am a backend developer but I have very less experience in designing. I went through themeforest for getting a good web design.i was a bit confused by their policy,I have a few doubts can you guys help me out? 1)Can I charge the client of editing this webpage and hosting ? 2)Can I create new page with the CSS files available in this project.(example there is a total of five page they are giving . I need to make a new page .is that possible?) 3)Should I revise this payment every year ? 4) difference between regular and extended licesnce.