Diane says that she has multiple Gmail accounts. She'd like to remove one. Leo says to go to that account and log out. Once she logs out, it won't be available. You can also remove it. Click on the picture and then manage the account. Once there, you can select delete or disconnect the account. You could also sign out of all accounts and then sign in to the account you want.
Also, go to myaccount.google.com and select delete my account. Make sure you are logged into the account you want to delete. Click on "data and personalization." Then delete your service or account. Then select delete your account. But be sure it's what you want to do because you will lose everything in that account.