I am using subscriber website for adding subscribers to site. In order to do this , service worker file is required to be added to site root directory. Below is the outline mentioned on subscriber.com-
Since your site is using the https protocol, you will want to upload a service worker file that will handle your site’s notification delivery. If you have access to your site’s root directory (usually via FTP), download the file below and upload it to the root of your site.
Request to help me or is there any other option to for push notification for site.
Urgent help required