get create project error please help

$ dart migrate --apply-changes --skip-import-check
Could not find a command named "migrate".

Usage: dart [arguments]

Global options:
-v, --verbose Show additional command output.
--version Print the Dart SDK version.
--enable-analytics Enable analytics.
--disable-analytics Disable analytics.
--suppress-analytics Disallow analytics for this `dart *` run without changing the analytics configuration.
-h, --help Print this usage information.

Available commands:
analyze Analyze Dart code in a directory.
compile Compile Dart to various formats.
create Create a new Dart project.
devtools Open DevTools (optionally connecting to an existing application).
doc Generate API documentation for Dart projects.
fix Apply automated fixes to Dart source code.
format Idiomatically format Dart source code.
info Show diagnostic information about the installed tooling.
pub Work with packages.
run Run a Dart program.
test Run tests for a project.

Run "dart help " for more information about a command.
See https://dart.dev/tools/dart-tool for detailed documentation.
✖ + error_unexpected ShellException(dart migrate --apply-changes --skip-import-check, exitCode 64, workingDirectory: /Users/fudongkai/Desktop/GitHub/flutterDemo/flutterg_get_x_demo)