You might not be using your Gmail account for a very long period of time and thus a result you forgot the password. Now you can’t access maps, docs, etc. So you would like to use Google Account Recovery via email in order to recover your account and get back all the features that Google offers. The password/credentials will be sent to the alternate email from where you can recover your original Google Account. https://www.my-accountrecovery.com/google-account-recovery/