Yup. Nobody knows how to succeed at anything. That's because success has many different elements, and one of them is luck - quite a bit is luck, actually.
It's the luck of genetics. The luck of being at the right place at the right time. The luck of having the right skills when needed.
Also, most of us don't know how we succeed. For instance, I am always asked how I manage to look so young. I have always looked a good 20 years younger than I am - without trying. Without bothering to look after my skin or do anything else.
Best answer I can come up with is combination of stress, constant exercise, reasonably good food, and the rest if genes. However, I don't know.
How do I write well? I don't know either. Never did writing courses. English is not my home language. Just was always able to write well from an early age.
How do I fail so constantly in everything I do? Took me a long time to figure some of that out as well. Asperger's combined with extreme abuse for more than 40 years of my life. Never really got over it.
How did I survive? Got lucky. Looks. Brains. Exceptional strength of character. All genes, I suppose. Luck.