Fred Trump gave his son Donald sums approaching $500 million. And anyone with that kind of backing who fails as The House in a casino is not a successful businessman. The bulk of Trump's money comes from side deal he made with the Apprentice producer Mark Burnett.
Read this piece from Fresh Air:
https://www.npr.org/2024/09/17/g-s1-23396/lucky-loser-dispels-the-myth-of-trump-as-a-self-made-billionaire