You won’t get tax 40% or whatever the rate is these days
You get MARGINAL TAX
For example:
$0-10,000 is 0%
$10,000-$20,000 10%
$20,000-60,000 20%
Etc… so on
$400,000+ 40%
Even if you are bill gate making $5 billion dollars
Your first $10k will be 0%

I just use simple number for easy example