Get Template
https://graph.facebook.com/{{Version}}/{{WABA-ID}}/message_templates
--------------------------------------------------------------------
Send Text Message
https://graph.facebook.com/{{Version}}/{{Phone-Number-ID}}/messages
Header
Content-Type:application/json
Body Message
{
    "messaging_product": "whatsapp",
    "to": "{{Recipient-Phone-Number}}",
    "type": "template",
    "template": {
        "name": "hello_world",
        "language": {
            "code": "en_US"
        }
    }
}
-------------------------------------------------------------------
Sending Template with changing the Parmeters
Body :
{
    "messaging_product": "whatsapp",
    "to": "966590015636",
    "type": "template",
    "template": {
        "name": "testparmeters",
        "language": {
            "code": "ar"
        },
        "components": [
                {
                    "type": "body",
                    "parameters": [
                        {
                            "type": "text",
                            "text": "12345"
                        },{
                            "type": "text",
                            "text": "sdsa"
          
                        },
                        {"type": "text",
            "text": "text-string"
          }
                    ]
                }
            ]
    }
}