Flutter android+postgresql

So I have created a mobile application using flutter but since iwant my database to be local I chose postgresql
But I never find any website explaining to me how to establish a connection between a flutter mobile application and postgresql.Can someone help me

Hello and welcome,

you will need a backend application, connected to the database, that exposes an API layer for the mobile application.

You could also check out PostgREST:

PostgREST is a standalone web server that turns your PostgreSQL database directly into a RESTful API.

Hth