Change of Conditions But Confused

[Mark5]

Hello everyone, pls your input is highly welcome. Thanks in advance!!

Questions...
1. Have anyone applied for change of conditions from study to Visitor within Canada and was issued a Visa?

2. What is the processing time for Visiting Visa within Canada?

3. How long is Visiting Visa valid for?

4. What are the possibility of getting the Visa.

Thanks!!