Flying to mainland PRC from the UK and returning from Hong Kong

I am planning on flying to Shanghai and then travel to other cities in PRC such as Beijing, before going to Hong Kong to visit and fly back from. Do I need to provide proof of where I am staying in PRC for the entire time I am in mainland PRC? Do I exclude the time that I am in Hong Kong for the application? Do I need to provide proof of flight to Hong Kong?

I haven't booked hotels and internal flights as of yet.