Hello Anjari,
Merely studying in Canada does not qualify you to apply for PR - you have to satisy some other conditions:
(1) If you live legally as an international student in Canada for 1 year, you can qualify to apply for PR under the FSW program. You have to satisy some work and language requirements. See http://www.cic.gc.ca/english/immigrate/skilled/apply-who.asp
(2) If you study in Canada for 2 years (at post-secondary level) and graduate from a recognized institution, you can apply under the Canadian Experience Class, but you need to obtain 1 year work experience after graduation and also satisfy the language requirements. See http://www.cic.gc.ca/english/immigrate/cec/graduates.asp
Essat
