Try to open it from samsung store link and click open. Try to open it from settings > apps > samsung noteshttps://apps.samsung.com/appquery/appDetail.as?appId=com.samsung.android.app.notes&cId=000006813128

Drag your screen from bottom to top to access all your applications. In the top search bar type notes and the icon will appear if installed, if not installed you'll be taken to samsung store to download it