Most travellers need a valid entry document such as an Electronic Travel Authorization (eTA) or a visa to visit Canada. There are two types of Visitor Visa's, a single-entry visa & a multiple-entry visa. Both are valid for a fixed period and cannot be used after they expire.
A single-entry visa allows you to come to Canada only once. After you leave Canada, excluding travel to the United States and St. Pierre and Miquelon, you will need a new visa to travel back to Canada. A multiple-entry visa on the other hand allows visitors to come and go from Canada, usually for six months at a time, without having to reapply. It is valid for up to 10 years, or one month before your passport expires, whichever comes first.
As with any type of visa, you will also be required to produce certain proofs that you are not a threat to Canada. This proof come in the form of a medical certificate proving that you are in good health, are not suffering from any communicable disease & do not carry any deadly virus, as well as a Police Clearance Certificate stating that you have no criminal or immigration-related convictions.
The Embassy will require a time period of 10-15 days to process your visitor visa application. It goes without saying that you need to make sure that you fill all forms without error & attach all valid documents to be submitted. The file would require a Fees of CAD $100 or Rs 4,950 for individual visa or CAD $500 or Rs 24,700 for family.
As part of Visa application, the applicants might have to go through an interview with an embassy official in which they have to convince the immigration officer that they will leave Canada at the end of their visit & also that they have enough money for their stay. The amount of money the applicant will need can vary. It depends on things such as duration of the stay & whether you will stay in a hotel, or with friends or relatives.