You can delete your yahoo account right now if you no longer wish to use it. Thereafter, you will not be able to access your yahoo account. If you too would like to delete your Yahoo account, follow my steps below:
Log in to your Yahoo account first
Click on the profile icon.
Next, select the privacy dashboard.
then, you see the delete my account option, click on it.
Last but not least, click on the continue deleting my account button.
This will delete your account once you follow the steps. More information is available in my post