I need to build a chrome extension

I need to build a chrome extension like this. Its a facebook messenger crm where we can create tags and list them and send bulk message to people inside the tag. [login to view URL] I need the complete source code and everything should be stored in local storage and the data should be able to be exported and imported using Json format. I don't need the portal login and sign-up feature. If you didn't understand the project let me know and we can get on a call to discuss about this.