Does dairy free milk help you grow like regular milk? Also, do they both cause acne?

Milk doesn't cause acne. Puberty causes acne. People who don't drink milk get acne just as often in adolescence as people who do. As for growing, it would depend on the dairy-free milk, but I would sooner put milk into my body over whatever clusterfuck of chemicals is in dairy-free milk, which is an oxymoron.

The sugar in milk (lactose) is one of two sugars that CANNOT make you fat like ALL the rest.

There are lots of non dairy milks.

Um, milk doesn't actually help us grow. It's laden with calories, deformed fat, cholestrerol and deformed proteins. It probably promotes immune activation leading to diabetes. We were never meant to drink milk beyond weaning. Putting some on cereal I suppose never hurt anyone, but milk should never be one's main beverage.