Pakistani Passport Holder - Require Visa for China from UK

Hi

I am currently working in UK but have Pakistaini passport.

I am planning to visit Shenzhen, but i think my company is booking me to travel to Hong Kong and then through ferry to China

But i am not sure that can i make this travel to Hong-Kong to Shenzhen and then back with only entry permit for China, or do i need to apply for China and Honkong separately.

I am planning for 3-4 days in total stay