My Baby is 18 months old but till now she is not saying anything not even mama or dada.
On her 15 month check up doctor told that she has some red flags for autism. the red flags are
1. she didn't point out her needs or clap or wave bye bye.
2. Didn't point out her interest.
3. does not respond to her name and seems like deaf some time.

But now she started to point out her needs, pointing her interest and respond to her name most of the time and she started to clap when I ask her and wave bye bye.
She can follow simple instruction like get me something, jump, dance etc. when I sing a song she do the actions. she can point out her 3 body parts correctly like head,tummy,hand. she pretend play well with the phone and the doll.

she is very happy child and never wants to be alone, always she wants me to be with her. she share her interest with me by bringing the things to me and she checks my face for her action. she got good eye contact.

She use to say mamamam but that's not me. its a babbling. she do thumb sucking. she use to watch TV for 4 hrs daily in english but english is a foreign language to her. now I have stoped her watching TV and thumb sucking. does it cause and speech delay in her?.
Are these are autism symptoms. should I be worried …. Please help me out.

I would suspect she was a little delayed due to the excess — ridiculously excessive — television. That sort of thing will cause developmental delays. she needs lots of one-on-one interaction. Keep going with the imaginative play, body part naming, etc.

It is not possible to read too much to a child, so make sure she's getting lots of story time. if books are new and she is not willing to sit still for long, focus on selling her on the idea that books are fun, for now — find books with pictures of stuff she likes, get her to come over and check out the pictures. Read the same pages over and over if that's what it takes to get her interested.

No she may just have a speech delay, it may be the conflict between two languages.

Since she is pointing out her needs and understands that you have a theory of mind (have your own thoughts), she does not have autism.

It sounds like she may have a simple speech delay.
Yes. Being exposed to a foreign language frequently can cause speech delay. however the delay is worth it because later on your child will be multi lingual and that will help them out their entire life.

Get her a developmental screening. Your doctor or your school district will be able to give you info on how to do this.
Whatever they tell you needs to be done. do it.

The main sign of autism is not being social. I mean like not even being social with parents. And not looking people in the eyes. it sounds to me like she is not autistic and just has a simple speech delay.