It can be viewed around the period of development of children at a young age 3. During this time, children with autism will show the characteristics of children with the disorder. Parents will begin to see that there is something wrong with their child's development.
Children with mild autism will be able to say the words, at most have a normal behavior, but there are different behaviors that indicate with autism, while children with severe autism are people difficult to deal with. If you need more information about autism then you can check this link https://www.juliasfriends.org/ and many other similar links.
They tend to have self-inflicted pain problems, the figures may not be able to communicate verbally and they have mood swings, not to engage in activities out or drastic social activities and other characteristics of a child with severe autism.
Therapists use a variety of educational tools and toys, as well as creating a game that will encourage communication, non-communicative abilities and other forms of examination and talking curriculum.
Children who suffer from severe autism may not be able to speak at all but progress varies case to case, Speech Therapy can work on one child or at other children with the same condition.
Talking with a doctor would be the best course of action in this situation. Talk therapy is not a cure guaranteed to children with autism. Only treatment that parents and guardians can opt for that might help or not for children's communication skills.