Thank you for your advice, but I finally managed to get pure Bicarb! It was not branded, just a plastic packet with some bicarb in it, after searching through four shops!
Let me share my successful experiment!!
I heated some of it on the kitchen stove, but it was a fail since the container I used was an oven mold and the mold melted
Okay, so when I used a normal container, I saw white fumes coming out of the bicarb. I came to know it was ready when white fumes started coming out of it. Wow. I had created pure Sodium Carbonate! To make sure, I took a little bit of it and added water, it felt a little soapy to touch. As another test, I tested the pH of it using some homemade turmeric pH testing method and compared it to the colour obtained by the sodium bicarb, and it was different! Now I surely have sodium carbonate!!!
Here's a fun experiment I did- I heated a solution of the Sodium carbonate (just mixed it with water) until it boiled and added a few pieces of aluminium foil. And then, the foil started fizzing and white fumes started coming out! I Am really happy that I could get all this to work. Can anyone give me written reactions for all of this ?