The extension of this visa is up to 10 years. However, at the time of entry into Canada, a border services officer will confirm how long you can stay.
If the length of stay granted at the time of entry into Canada is 2 years, and you wish to benefit from a longer stay, you will have to leave Canada before the end of your authorized stay and re-enter Canada after July 4, 2022. The border services officer can grant you a stay of up to 5 years if you meet all the requirements.