How can I get gas with money?

I'm curious, how does one actually go about purchasing gas using money? Is it as simple as driving up to the pump, inserting cash, and filling up the tank? Or is there a more intricate process involved? Perhaps there are different methods depending on the type of payment one prefers, like credit cards or debit cards. I'm really interested in understanding the various ways one can acquire gasoline with financial means, and what the most convenient and cost-effective methods might be. Can you provide some insight into this topic?