Hi
If you want to apply online pls follow:
http://www.cic.gc.ca/english/my_application/apply_online.asp
It will ask-
What are you applying for ?
-Select drop down button and select visitor visa
-Fill out online questionnaires
-Then click on start for online questionnaires
Click on Check Eligibility
-Then you will see series of questionnaire- select answer from drop down menu
......