Smart Contract - Lending (Example)

Hi everyone,

I’m fairly new to the space and while learning about smart contracts I saw someone mention how one of the functions is to lend money.

It mentioned how with the correct IF / ELSE functions, you could loan the money, make a profit, and return it instantly so I wanted to check if someone could tell me where I can find examples of those smart contracts?

I understand it’s not an easy process, but would like to dive down into that rabbit hole so any help is much appreciated!