Communication between application and webserver [closed]

as my question got deleted yesterday I tried a little step. I'd like to code an application, where I can create a own account, search other account, add them and text them a message.

I created an apache server with a MySQL Database using XAMPP. And I already made a little application in Android Studio. I created a registration side, where i create an account by a http request to the server. It works. I can also login to an account by a http request, where I search through the database with a querry and check username and pw.

Now my question. Is this the right way to do this? When I create an account, do I have to create several databases for each account? For friend requests, friends, maybe blockes accounts etc.? After that, when I start to code a conversation. Is there also a database which includes all messages and every phone asks every second if something changed? Honestly it's so hard to find something in the internet how to code an application like that from scratch.

source https://stackoverflow.com/questions/73429358/communication-between-application-and-webserver