Send data from Android Studio App to Sparkfun Thing Plus - ESP32 WROOM

Hello everyone !! I have a project in mind and I am trying to configure how to connect my android app (created on Android Studio) with my Sparkfun Thing plus EPS32 - WROOM via Bluetooth in order to send some strings to my EPS32. After that I will display them in an OLED display.

Can anyone help me how to do this ??? I already tried the ESP32 BLE Arduino Examples but I could not understand how to adjust this code to my app.

Thank you very much !!