There's only one thing I've ever needed to know about credit cards.
If I pay them off on time in full every month, they do nothing but benefit me. I have access to free money until the month ends when my bank autopays the credit card balance. Meanwhile, the bank is paying me next to no interest for holding my cash.
If retailers have to charge more for goods and services because of fees they pay for each card transaction, just think how few transactions and customers they would have without accepting credit cards. More businesses will close than already have been closed up in the pandemic and inflationary environment.
What should be taught at a young age is that one should not spend above one's income, and credit cards are an easy trap for people who don't live by that lesson.