hi, i live in canada montreal and my nationality is iraq and i have permenant residence in canada

You can apply for a tourist L type to visit a fair there. The required documents include your passport and its photocopy, the application form and a passport-style photo, your ID card and its copy, your residence permit in Canada, proof of financial standing, round trip air tickets and hotel reservation. Maybe an invitation letter from a duly authorized unit is required, too.
The consular officers may require you to provide other relevant materials.
You should submit your application to the CVASC in Montreal to apply for it.