The code wont start

every time i try to start this message apears

Failed to resolve the Android SDK path. Default install location not found: C:\Users\Instrutor\AppData\Local\Android\Sdk. Use ANDROID_HOME to set the Android SDK location.
Failed to resolve the Android SDK path. Default install location not found: C:\Users\Instrutor\AppData\Local\Android\Sdk. Use ANDROID_HOME to set the Android SDK location.