Is it permissible not to repay the student loan taken from the Canadian government, on the grounds that these governments fund the attack against Muslims in Chechnya?

If the loan contains usury, it must be canceled if possible. One must repent and seek forgiveness for this act and resolve not to return to it. If the loan is established as a debt, it must be paid, while trying to avoid paying the usurious increase. If you cannot avoid it, then pay it under duress and with aversion. As for governments funding attacks against Muslims, anything that aids falsehood or fights against Muslims is forbidden.