The error message indicates that “new_app_App” is not a valid Dart package name. Dart package names must follow certain conventions outlined in the Dart documentation.

Here are the rules for valid Dart package names:

1. Must be a valid Dart identifier, which means it should consist of alphanumeric characters and underscores.
2. Must not start with a digit.
3. Cannot be a reserved word in Dart.

To fix this issue, choose a Dart package name that adheres to these rules. For example, you could use a name like “new_app” or “newApp” instead of “new_app_App“. Then, try running the flutter create command again.

Example:

flutter create -i objc -a java new_app