feat:Enhance Newsletter Subscription with Validations and Confirmation

## Description

**Is your feature request related to a problem? Please describe.**
The current state of the Newsletter feature lacks necessary validations and confirmation, leaving room for improvement. This issue proposes to implement enhancements that ensure proper validation checks during subscription and provide users with a confirmation (like a pop-up on the screen that they are subscribed)

**Describe the solution you'd like**
This issue proposes to implement enhancements that ensure proper validation checks during subscription and provide users with a confirmation (like a pop-up on the screen that they are subscribed)

**Describe alternatives you've considered**
The proposed resolution fixes the problem.