You can check the name of physicians and where to visit them from here:
http://www.cic.gc.ca/pp-md/pp-list.aspx. They will perhaps provide you with a slip of completion of a medical examination for you to submit with your application. I am not sure though as I haven't done my medical yet. I suggest you read in detail the information provided in the abovementioned website. I don't know about college and university wise differences. But, visa success rate for the study permit is extremely poor for Nepal. I was shocked to see the data: 9-17% (
http://www.cic.gc.ca/opendata-donneesouvertes/data/IRCC_TRproc_0003_E.xls). But, no idea about college-university difference though.