Difference between autism and delay development

A. See It is basically a mental condition only where in when you say delayed growth the brain is little behind The current age of your child if your child is about a 1 1/2 to 2 years of age the child is going to act like a one-year-old child you know like that if the difference would be anything I’m just giving an example and autism is actually a situation when a child’s brain is quite behind in terms of development that’s quite a critical condition as well