How to Integrate Gupshup with WhatsApp for One-to-One and Group Messaging, and Send Messages Through a Website?

Question

I'm currently working on integrating Gupshup with WhatsApp for various messaging purposes. I'd like to achieve the following:

Send one-to-one messages to WhatsApp users.

Create a WhatsApp group and send messages to that group.

Send messages through my website to users, I have just their phone numbers.

I've already set up a Gupshup account and am using the sandbox environment for testing. Here's what I have so far:

Steps Taken:

Account Setup:

Created a Gupshup account.

Accessed the WhatsApp sandbox environment.

Obtained the sandbox phone number and API key.

and able to send messages through sandbox to my whatsapp by connecting the Opt-In QR Scanner

I'm not sure how to proceed with creating a WhatsApp group and sending messages to the group using Gupshup. Could anyone provide guidance or example code for this?

Question:

Creating Groups: How can I create a WhatsApp group via the Gupshup API and send messages to the group?

I am looking for WhatsApp integration for my e-learning site where, whenever a teacher creates a classroom, test, session, etc., all the students in that classroom receive a message on whatsapp.

Any detailed guidance or example code snippets would be greatly appreciated! Thank you in advance for your help!