The beauty of Jack-Jack is that he's just a baby and hardly aware of his powers.
When he gets mad, he discovers it.
When he's happy, he finds it, too.
And when he gets to know those powers, he becomes a quick adept.
And he's just a baby.
While his parents have one power each, this tiny creature's got 17.
Some articles you may wish to read about his power:
"All 17 Jack-Jack powers in the Incredibles 2, explained"
"Jack-Jack powers up in Disney-Pixar's Incredibles 2"
"What are Jack-Jack's powers? Here's what we know about the Incredibles baby"