Today I try to answer one question:
Is it possible to work for someone else and become a self-made billionaire?

The answer is DEFINITELY

Here is my youtube link
https://www.youtube.com/watch?v=JDIfJkn1w18
There are plenty such examples 

About 2% of selfmade billionaires never founded their own business. 

Let's start with 7 famous examples here, in descending order of wealth

Example #1  Steve Balmer (on the right)

CEO of Microsoft 2000 to 2014

Example #2  Eric Schmidt

Eric Schmidt was CEO of Google

Example #3  Joseph Tsai

Joseph Tsai is Chairman of M&A (Merger and Acquisition) of Alibaba

Example #4  Meg Whitman 

She is currently CEO of HP (Hewlett Packard)

She was CEO of eBay for 10 years 

Example #5  Charles Simonyi (on the left)

He is a Hungarian Immigrant who got his PhD in Computer Science from Stanford University

He was Chief Engineer of Window 95,  Microsoft Word and Microsoft Excel

Example #6  Jonathan Gray

At age 47, he is Head of Real Estate at Blackstone 
Private Equity

Example #7  Sheryl  Sandberg

At age 47, she is COO (Chief Operating Officer) of Microsoft