How do I create a chat api for the ios and Android using AWS?

I have no prior server experience.AWS server is what I'm using for my project.
I simply want to create a chat api for iOS and Android.

How can I create a chat api on AWS, step by step?

Suggest me with your thoughts

That's not an easy question to answer. Do you want to build the SDK yourself or use something like AWS Chime?

There are a number of ways of hosting a Swift application on AWS - I suggest starting at the Swift.org guides and go from there