Autistic children act differently to neurotypical children because they are different.
Autistic people experience the world and interact with the world differently to neurotypical people. Autistic people lack social and communication skills of neurotypical people, and if you view neurotypical behaviour as the norm or ideal it looks as though autistic people are 'different'.
No, not all autistic people act the same - autistic people are as different and varied as neurotypical people. Like with neurotypical people all autistic people will share common traits, but once you meet one autistic person then you've met one autistic person...we're all very different.
They can.
Kids with autism can 'freak out' when other kids cry, all autistic people are different. Autistic people have lower levels of cogitative empathy, meaning that they may struggle to recognise emotions in others or acting appropriately in response compared to neurotypical people, however autistic people have significantly higher levels of affective or 'true' empathy compared to neurotypical people. This means that autistic people can be very sensitive to the emotions of others, when they are able to recognise others are upset it can make autistic people very upset too.
Autistic kids and teens do want friends, the idea that autistic people are anti-social is false. Autistic people often want friends but struggle to make and maintain friendships.
fat but
No, most Autistic children won't learn ASL.Although there are Autistic children who may be non-verbal or deaf so will learn ASL as a means of communication, not all Autistic people need to use sign language to communicate. Also of course not all Autistic people are American so will learn different languages.
Define what you mean by 'act normal', or for that matter how you define normal.Many Autistic people attempt to 'pass' as neurotypical as a means of survival, but as Autism acceptance increases there's less of a need to do this - there's nothing wrong with being Autistic, continuing to act Autistic is not a problem and shouldn't be treat as something abnormal.
Feral children may act similar to severally autistic children, but the conditions are different. Autism is caused by genetics, feralism is caused by extreme neglect, so feral children are technically not autistic, though I've seen theories that say only autistic children are capable of figuring out on how to live in the wild, and therefor all feral would be autistic.
Yes
Yes, of course Autistic children will cuss.Autistic children are little different to allistic or neurotypical children, if they are verbal then they will potentially cuss just the same as any other children. There is nothing about autism that would prevent an Autistic child from cussing or make them less likely to cuss.
Different autistic individuals have different levels of intelligence. So, it depends on the individual.
You can't - autism is an absolute, you are either autistic or you are not and there is no way that a person can become 'less autistic'. A person with autism can improve in areas such as commnuication, social skills, and functioning, this tends to happen naturally as autistic people get older and learn new skills, but it is helped by supporting and understanding the autistic person.