Cannot run with sound null safety, because the following dependencies don't support null safety: - package:english_words
Run/Debug configurations
Additional run args: --no-sound-null-safety 입력
or
pubspec.yaml 을
sdk 버전 변경
기존 sdk 2.15.0 -> 2.7.0 으로 변경
sdk: ">=2.7.0 <3.0.0"