WhatsApp API link to Cloud-based POS- API Real-time

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WhatsApp API link to Cloud-based POS- API Real-time

I like to set up Real-time communication between POS with WhatsApp current numbers & the same style of WhatsApp chat, the way we follow on mobile /pc.

Example
Once my customer buys products from a POS moment invoice save on Real-time invoice copy PDF (POS API will give text invoice details needed to convert in PDF) & all products image there in the invoice (the image will get from POS API) must go to the customer on her/his WhatsApp which is linked to invoice. Along with the prefix text MSG.
The same number will come in my chat at the same time. Name & number auto-save to google contacts ABCDEF {name of customer} (CUSTOMER {prefix for all} number save ABCDEF CUSTOMER)

See one example below.
MSG go With two options as below.
1. “Get 10% Off With Future Product Updates”
2. “No Future Updates”
( If some click on 1 auto msg go) “You Are Eligible For 10% Off Lifetime From The Rup Art Shop” coupon code: WELCOME10 Buy from the shop or online www.
( If some click on 2 auto msg go) “Thanks For Update” (number deleted from google)
Customer-click any one of these.

If the number is not a WhatsApp number then one system error logs on the dashboard with POS Shop Location (Outlets) Date invoice number & name come in excel format.
I don't have WhatsApp API I have API for my POS system to be linked with WhatsApp
I don't want a WhatsApp chatbot. I need normal WhatsApp chat work.
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