Yes weither a bowl, tank or pond if you have chlorine/chlorimine in your water you need to use a dechlorinator. Hopefully the bowl has a filter and a heater. Bettas are still fish and have the same basic needs.
You might tell your friend that the water needs to be changed every day (at least once, more preferably) if you keep a fish in a bowl. A tank with a filter would be better .. at least 2.5 gallons, but 5 gallons is better. Bettas need warmer water so they need a larger space so they can have a heater if the temps are lower than 78 or so.