What is the ruling on taking study assistance from the Canadian government, part of which is classified as a grant and part as a loan, knowing that the government pays the interest on the loan throughout the study period, and interest is not requested until after its completion?

Usury is one of the gravest prohibitions, and it is not permissible except in cases of extreme necessity, such as not having enough food, drink, and clothing for yourself and those you support. If you are compelled to this extent, then it is permissible for you to take it; otherwise, it is not permissible.