How to unlock a Gmail account for which I have forgotten my username?

First of all open your Gmail website through an internet browser then click “need help?” then click the appropriate option “I don’t know my user name” after that click “continue” then in the fields enter the first name as well as the last name then click “submit” then click on the checkbox against “I am not a robot” then enter the text in the image seen on the screen after that click “verify” then click “submit”.