Use the below steps to download Norton Antivirus from Norton.com/setup:
Launch a web browser on your computer and visit www.norton.com/setup.
If it’s your first time with Norton, then you need to create yourself a new Norton Account. Or if you have used Norton services before then you can use your previous existing Norton Account.
Once you have created the account, hit the Sing in button, and enter your account credentials.
Select your payment method and finish the payment.