visa on arrival in HK and Guangzhou??

Dear, there is no VOA in HK, but don’t worry, Indian passport holders are allowed to enter HK freely for a stay of no more than 14 days.
There is no VOA in Guangzhou either, so you should apply for an entry permit in India before your trip.
The best way to travel from HK to Guangzhou is to take Guangzhou-HK Train, runs between Guangzhou East Railway Station and HK Hung Hom Railway Station with the duration of about two hours.