What is a realistic spend:traffic: ratio in regards to Google ads

May be a ridiculous question, and if it is just say so, but I was just wondering what the most realistic amount of organic traffic is that you’re likely to gain per daily/weekly spend on Google ads. With this question I’m looking to exclude bots if that’s even possible.

Thanks!

Edit: Also, Is it worth hiring someone on Fiverr to run said Google ads?