Is PIO Card and Dual Citizenship for India same thing? Also what is the procedure for obtaining the same.

PIO card is not citizenship. PIO card is like u can say something like PR card that you don’t need visa to go India and can live for long time if you want. PIO card is quite good to do anything in India so sometimes no need for Indian citizenship to keep.

PIO card is something like a PR card (in fact, it is a booklet and not a card). It has an expiry date. Also, you require registration after your arrival in India in case you are planning on staying in India for more than 6 months.

OCI card (again, it is a booklet) does not have an expiry date - it is valid for lifelong and does not require registration after your arrival in India even if you are planning on staying in India for more than 6 months.

I would like to add that overseas citizenship of India is nowhere close to Dual citizenship as dual citizenship entitles you to passport of 2 countries and is legally allowed by some countries

Dual may have some trouble also. If you stuck in war at home country/other country or in criminal offense then it's not easy for Canada to represent/help you.