I intend to stay at Hongkong instead of kowloon. Which is easiest n fastest way from Shenzhen?

You are advised to enter Hong Kong from Luohu Port. Then take East Rail Line from Lo Wu Station to Kowloon Tong Station. Transfer to Kwun Tong Ling to Mong Kok Station and Tsuen Wan Line to Central Sattion (Close to Hong Kong Station). The whole way takes around 70 minutes. And the ticket fare is 47.6 HKD per person.