You can apply online for Canadian visa, and they will request to send your passport and other documents later through mail. It used to take 6 weeks to 9 weeks for the whole visa process, but currently it shows it shows the processing time is 13 days that means 1 months to get visa in your hand from the date of your application submission. Don't know about the chances of getting visa for US visitor. (I would say they will give to most of applicant).

Best of luck