If he's not an orphan - then you cannot sponsor him for PR.
He could apply for a study permit to attend school in Canada. To be approved, you will need to find a local school willing to accept him. Since he will be a foreign student, he will have to pay an annual tuition fee of approximately $14K per year (this is for public school, it will be more for private school). When his parents submit the study permit application, they will have to demonstrate that they have sufficient funds to cover the $14K/year tuition costs + living expenses.