You’re incorrect. Within a couple of years is for 12-13 year olds. Within 5 years is 14-15, while 16 years can consent to all ages (except for those cases where there’s a relationship of trust, authority or dependency).

Canada's age of consent The age of consent to sexual activity is 16 years. In some cases, the age of consent is higher (for example, when there is a relationship of trust, authority or dependency).

In other words, a person must be at least 16 years old to be able to legally agree to sexual activity.

Close in age exceptions A 14 or 15 year old can consent to sexual activity as long as the partner is less than five years older and there is no relationship of trust, authority or dependency or any other exploitation of the young person. This means that if the partner is 5 years or older than the 14 or 15 year old, any sexual activity is a criminal offence.

There is also a "close in age" exception for 12 and 13 year olds. A 12 or 13 year old can consent to sexual activity with a partner as long as the partner is less than two years older and there is no relationship of trust, authority or dependency or any other exploitation of the young person. This means that if the partner is 2 years or older than the 12 or 13 year old, any sexual activity is a criminal offence.

Source: https://www.justice.gc.ca/eng/rp-pr/other-autre/clp/faq.html