Non profit means no profit. Salaries, rent, etc are not paid from profit.

That is fundamentally what profit is, revenue less expenses. By definition, profit is money that does not have anywhere to go in a business, and so gets distributed to stake holders of the company.

I mean, non profits exist. Of course it’s not the case for Amazon, but you don’t need to profit in order to exist as a company, and people still get to make money.

Yes, but revenue pays for things like salaries, advertising, etc.