He also has no real idea of how govt operates and no interest in finding out. I doubt he understands basic eighth grade civics about the operation of each branch and what's in the Constitution.
He also has no core principles or beliefs. To the extent he has any minimal ones, they tend toward the left. In and of itself that's not disqualifying. He is impulsive and lacks mature judgment. He is also petty and vindictive to the nth degree. He is not good at details or organization. He's not a great businessman. He is a great real estate idea guy and developer. There is a big difference between those two. He is also a great self promoter and reality TV guy. None of these skills equal a chief executive of the most powerful nation on earth. The things you mention about him are simply visible symptoms and evidence of this.
Finally, he will demagogue up any issue simply to get elected. He no more believes this immigration crap than I do. Historically, he's been a moderate on the subject who took Romney to task over it in 2012. The fact he will say anything to get elected is very disturbing when coupled with the above.
In short, he's unqualified.