Do I need transit visa or any to travel via Hongkong?

1.I am holding Indian passport and got canadian student type. Booked my flight tickets from India to vancouver, Canada via HK. Layover time will be for around 12 hrs and planning to visit city.So need to know whether I need to get transit type or any.
2.How much HK currency I need If I wish to tour city for around 8 hrs.I will be carrying Indian and Canadian Currency for exchange.Hope this will work.