안드로이드에 expo go 설치되었고, qr로 연동되어서 강사님하는데로 vscode에서 App.js 코드변경시켜주는데 핸드폰에선 전혀 작동하지 않습니다.

이제는 qr코드로 찍어지지가 않는데? 뭐가 잘못되었을까요? expo start 실행시키고 폰이 안드로이드라 a를 눌렀더니 에러메세지가 떠요

https://developer.android.com/studio/run/device.html#developer-device-options. If you are using Genymotion go to Settings -> ADB, select "Use custom Android SDK tools", and point it at your Android SDK directory.
Error: No Android connected device found, and no emulators could be started automatically.
Please connect a device or create an emulator (https://docs.expo.dev/workflow/android-studio-emulator).Then follow the instructions here to enable USB debugging:
https://developer.android.com/studio/run/device.html#developer-device-options. If you are using Genymotion go to Settings -> ADB, select "Use custom Android SDK tools", and point it at your Android SDK directory.    at getAllAvailableDevicesAsync (C:\Users\ASUS\AppData\Roaming\npm\node_modules\expo-cli\node_modules\xdl\src\Android.ts:118:11)    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at Object.openProjectAsync (C:\Users\ASUS\AppData\Roaming\npm\node_modules\expo-cli\node_modules\xdl\src\Android.ts:938:21)
    at handleKeypressAsync (C:\Users\ASUS\AppData\Roaming\npm\node_modules\expo-cli\src\commands\start\TerminalUI.ts:305:27)    at ReadStream.handleKeypress (C:\Users\ASUS\AppData\Roaming\npm\node_modules\expo-cli\src\commands\start\TerminalUI.ts:269:7)