Help me to create app for automaatic connection at bluetooth

Greetings! I’m a newbie to writing her first app.
I am making an app which, by means of hc05, commands the opening of the access gate to the garage. if possible I would like to do everything with a single button that connects to the bluetooth automatically without opening the bluetooth drop-down menu and commands the opening. My gratitude to those who will help me. Greetings to all!