Build a small android chat application

We need a small Android app made in Flutter using Jetpack.
we need chat app using socket programming connecting to MySQL and MongoDB.
All other basic chat functions are needed like:
One to one chat
One to many
Groups chat
Attachments/files upload/etc
Notifications from the web platform
Registration/Login/Forgot password


We need this in 20 days and our budget is 200$

Designs for app will be provided.

Thanks