Not a dumb question at all!
Maybe the boys can give you more insight but from my understanding body types like ectomorph, mesomorph and endomorph are real and can help guide you with what to eat etc. Ectos are usually lean and might need more calories to bulk up. Mesos are naturally muscular and can generally balance their intake well. Endos gain weight easier so they may need to watch their carb intake. To figure out your type, just look at how your body naturally responds to food and training. It’s not strict science but knowing your type I think can help.