Yes, Tesco does sell helium canisters. You can find them in the party section of most stores.
They are often used to fill balloons for parties and celebrations. Helium is a gas that is lighter than air, so it makes the balloons float.
You can also buy helium canisters online from the Tesco website. They come in different sizes, so you can choose the one that best suits your needs.
Prices start at around £10 for a small canister, and go up to £50 for a large one.
When buying a helium canister, you should also buy some balloon inflation gloves. These will help to protect your hands from the cold gas.
You should also read the instructions carefully before using the canister, as they can be dangerous if used incorrectly.
In conclusion, yes Tesco does sell helium canisters and they are available in most stores as well as online. They come in different sizes and prices start at around £10.