Help regarding subscription products renewal

My company sells many products on a subscription basis.

For example, if a product has a subscription period of 3 years, I want a system where, as the subscription is about to expire, renewal notifications are sent at three intervals: 1 month before, 15 days before, and 7 days before expiry.

These notifications should be sent to:

  • The CEO
  • The person who closed the deal
  • The purchasing person

Additionally, the renewal notifications should be visible on WhatsApp, email, and the CRM dashboard.