You would have to do it yourself with Zapier or Make.

Here’s the logic you need to set up in Zapier/Make:

New Order in Shopify (make sure you have the phone number) => Create new subscriber in Manychat => send the necessary info (e.g. order data - you save that in Custom Fields) => trigger the flow for that user (the one with the WhatsApp template).

subscriber cant be added using zapier

Yes you can, you need to use Manychat's API and Zapier's Webhook Request

https://zapier.com/apps/webhook/integrations

https://api.manychat.com/swagger#/

Is that also the way to import data from shopify as custom field formatted as date using zappier?

I manage using zappier to import custom field to existing subscriber in many chat, but I can only import a date from shopify as text, not as date, so I can not use it afterwards to send message using “the event thing” at that specific date 

Yeap you can import dates as well with this.

@JOSE SANCHEZ if you need help setting this up or debugging, book a call here and I can walk you through all the details ;)