by As of October 17, 2018 Canadians 18+ years old (19+ in BC) can legally purchase up to 30 grams (or the equivalent) at any one time. In BC, 1 gram oil is equivalent to 15 grams of dry flower or 1 seed. For example one could purchase 30 g dry flower or 14g dry flower, 1g oil, and 1 seed on a given day. So in a nutshell yes!
That said if you do. have a medical condition that you would like to treat with Cannabis you should pursue medical access through one of the federally approved and medically licensed providers.
When in doubt check the cannabis regulations in your Province by visiting the Canada.ca website