WhatsApp Business API Integration

I'm looking to integrate WhatsApp Business API into my app (available on both iOS and Android) to send notifications to new and existing users. The notifications will include transactional messages, promotional messages, and service updates, similar to how Makemytrip sends trip-related details to its customers.

Requirements:
- Setup WhatsApp Business API access
- Link my Meta Business Manager & phone number
- Create one message template for testing the integration
- Walk me through the process to create more templates
- Provide code snippet/webhook to receive delivery status

Ideal Skills and Experience:
- Experience with WhatsApp Business API integration
- Proficiency in REST API
- Familiarity with Meta Business Manager
- Strong coding skills to provide necessary snippets and webhooks
- Good communication skills for walkthroughs

Please ensure the project is completed within 3–7 days.