Too young!! Baby needs control of its head before beginning to eat from a spoon. Your putting too much food on the spoon. Cereal is a touch too thick and you are feeding too fast, baby needs a minute to swallow!!
OBVIOUSLY not too young. As long as they are eating and not pushing the food out with their tongue, it’s perfectly fine. And you have no idea what the circumstances are! What if the doctor said to start feeding solids? Between 4 & 6 months has always been the standard. I agree the neck should be supported, but other than that… FEED AWAY!!!
You can mess up a baby's digestive system sometimes if they are too young! That's why most of the time it's best to wait until they sit alone and hold their head up and steady.