Do I have to pay the full one-year fees from India before applying for a Canadian student visa?

Not always. For Canada, you are often strongly advised to pay at least the first year tuition fees before applying, especially because it strengthens your visa file and is commonly expected in cases of students applying to diploma or post gradaute diploma programs. Some students (especially bachelors or Masters degree applicants to universities) may apply after paying only a deposit, but full first-year payment is generally the safer and stronger approach for diploma/PG diploma applicants.