To generate SHA-1 code for your Flutter project, you can follow these steps:

1. Open your Flutter project in Android Studio.

2. Navigate to the terminal located at the bottom of your project.

3. Type the command `cd android` in the terminal and press Enter.

4. Type the command `./gradlew signingReport` in the terminal and press Enter.

5. Scroll down to the `Variant: debug` section to find the SHA-1 key or SHA-256 key.

as shown in the picture downblow

Please note that SHA-1 is considered insecure and should not be used for new applications. SHA-256 is the recommended cryptographic hash function for generating secure digital signatures and message authentication codes. You can generate both SHA-1 and SHA-256 keys using the same command in Flutter apps.