DGI48, you'll need to concentrate on the sciences to get in as a medic, even in the reserves. You should be taking grade 11 and 12 biology as a minimum, and chem or physics won't hurt either.
While the CF will give you all the training to be employable as a reserve medical technician, they won't currently provide all the training you'll need if you hope to deploy operationally, except in rare circumstances. That normally requires that you attend a college and get yourself a Primary Care Paramedic diploma or certificate, and then face a provincial licensing board.
With all your science courses done, and all other entry requirements met, the Reg F may take you and train you "right from scratch."
I hope this helps,
DF