Understanding the way of lending money

[Jackson Rottenberg]

I still can't wrap my head around the idea of hard money and private money when it comes to paying it back. My understanding is that I will get a loan from either source and pay the interest every month and when I refinance the home I will pay the lender back the initial investment. How does one truly do this with no money ?  How would I even pay the month to month costs when i don't have enough money coming in to start off with?