US requirements for Catholics fasting in Lent

Citation please? While now I don’t believe in god, I was raised in a Roman Catholic household in the US (I was born in 1961). I never heard anything about abstaining from eating meat (outside of fish) on Fridays outside of Lent. (And of course also Ash Wednesday.) I just never heard anything as a kid that eating a cheeseburger in July could be inappropriate.