Toronto to Shanghai. Shanghai to singapore and back to Shanghai , leave from Shanghai to Toronto

I need some information before I book my ticket, I am Canadian would like to get visa and stay for few day in China before we go to Singapore, how can I get 144 hr free transit to stay for few day
my plan
1. get ticket Toronto - Shanghai and stay for few day Shanghai -singapore for week then back to Shanghai stay for few day and leave to Toronto (my ticket will be tor-pvd return ticket pvd to Singapore one ticket Singapore back to pvd one ticket


2. Toronto -hongkong from honkong get ticket to Shanghai stop and to Singapore back to honkong
which one will work, thx