Normally people earn a bachelor's degree in business (BA, BBA, BCom) and then complete the CPA program. It is possible to have a BA or BSc in another discipline and then go back and take any required CPA business or accounting courses either from the Provincial CPA body itself or from a university or college.
I would recommend a co-op program where possible as that helps you secure a CPA training position. However, it is just as possible to find a training position without a co-op job history.
There is a shortage of accountants so if you have good grades, it shouldn't be hard to find a training position.