Article: Use the link or type the URL in a web browser. If your email or phone number isn't filled in automatically, type it into the labeled field and click on Next.  If you don't remember any of the passwords you've used before, click on Try a different question at the bottom of the gray box. Continue clicking on Try a different question until you come across one that you can answer, answer it, then click on Next. You'll be asked to do one of the following:  Confirm a text to the phone number associated with your Gmail account; Confirm a message to the email associated with your Gmail account; Confirm the email of your recovery email account if you've set one up; or Enter an email that you can check immediately.     Your password has been recovered and you can sign into Gmail with it.  If you were unable to enter a previous password or receive a message at your associated phone number, email, or recovery email, you'll be asked to "briefly tell us why you can’t access your account." Enter a reason and click on Submit. Google will get back to you in 3-5 business days.

What is a summary?
Go to https://mail.google.com. Click on Forgot password? below the password field. Enter the last password you remember and click on Next. Follow the on-screen instructions. Open the applicable email or text message from Google. Enter the verification code in the message in the field on the screen. Enter a new password and confirm it in the labeled fields. Click on Change password. Click on Continue.