Download the Featured Chrome Extension "Gmail Unsubscribe" on your Chrome Browser
Once Downloaded
Click on the Extension and Login using your email
Open your Gmail Account.
Now you will see Unsubscribe Button
Select the emails or Select all and click on Unsubscribe
It will show you a list of emails. Remove the important emails
Click on Unsubscribe and your emails will be cleaned.
As a free trial, you will have 5 times to unsubscribe. So select as many emails as possible everytime