I'm pretty sure there is a Pakistani community in Calgary... it's quite a multicultural city.
Captain Forest is right... you will need a permit, which will cost money. Also, Calgary, like the rest of Canada (except maybe for Victoria, haha), has winter and I don't think many people will be wanting their hands painted on the street in January. You would be able to do that only say, from May to September. However, if you're lucky, during those months you might get a fair bit of business. I myself am an artist and although I have my own studio, I sell a lot of my work at street fairs in the summer and early autumn. And in the winter I go to artisan and craft shows. Each street fair and artisan show has a fee for vendors though - usually 50 dollars or more. As an artist I make enough money to live off of but it's not lots. I think most people in Canada are artists because they really want to be, and not for the money. There are much more profitable jobs to be had.
It might be a good idea for you to contact a local immigrant society once you get to Calgary. We have two such societies where I live in Saskatchewan (that I know of, anyways) which help immigrants with finding jobs, friends, a place to live, etc. You could start with the Immigrant Aid Society of Calgary:
http://www.calgaryimmigrantaid.ca/
I'm sure there are many other organizations, too. Also you could join a mosque, church or another religious organization in order to meet people.
Good luck to you!