Some websites and apps allows Google account for sign up, after some period most of them will forget this. These accounts are linked with Google account.Deseat.me will help you to find to accounts and services you have ever created an account for. This service helps to find linked accounts and delete linked accounts.
To find linked accounts simply sign up in Deseat.me via your Google account. It will display linked account list here you can easily delete. For some popular services, you can click the “delete” button to directly go to the place where you can shut down your account.