What’s the difference between strabismus and lazy eye? I though they were the same things, but now i’m reading that they’re not and they can each cause the other. I’m confused!

Not the same. Strabismus means the eyes are crossed - when eyes are crossed in a young child the brain will get confused and ignore the crossed eye, leading to amblyopia or "lazy eye." other causes of a lazy eye can be a very high prescription in one eye that is asymmetric; again the brain starts to ignore the eye with the high prescription (because the image is blurred) and therefore develops amblyopia.
"Lazy. "lazy eye" is a lay term for amblyopia, where one eye is favored over the other by the brain. There are many reasons why this could happen, one of them is the presence of strabismus (eye turn). So you are correct in that strabismus is one of the causes of amblyopia.