To delete your Google account, log in to your account and go to data and personalisation and click “Delete your account” form the “Delete a service or account” section.
Here are the steps in detail to delete your Google account.
Step 1
Go to google.com and sign in to the account that you would like to delete.

Step 2
Click on your profile picture and select “Manage your Google Account”

Step 3
In the accounts settings page, navigate to the “Data & Personalisation” section.

Step 4
Click “Delete a service or your account”

Step 5
Now click “Delete your account” from Delete a service or your account section.

That’s it.
You have successfully deleted your Google account.