Most likely impossible. You need a work permit in order to be able to work. To qualify to apply for a work permit, you would first need to secure a full time job offer from a Canadian employer. Next, that employer would need to obtain something called an LMIA (approval to hire a foreign worker). To obtain an LMIA, the employer will first have to advertise the job for at least a month to prove no Canadian could be found for the role. Next, the employer will have to submit the LMIA application for processing along with a $1K fee. Processing of the LMIA application can take as long as four months. If the LMIA is approved (no guarantee it will be - it may be refused if the employer should have been able to find a Canadian for the role) - then you can apply for a closed work permit tied to that specific employer and job.
Most employers aren't willing to go through this process given the expense, time it takes and paperwork required - especially for a job like a restaurant worker. Also, it's quite possible the LMIA for this kind of job will be refused since there are plenty of Canadians around to take the role.
