Whastapp send mess

https://wa.me/393123456789?text=Sono%20interessato%20alla%20macchina%20in%20vendita

Entering this in url opens Whatsapp

how do instead of writing the number tell him to take that from an example database

(Db_negozi.whatsapp)

what should I insert as an action ???

Thanks

FAQ WHATSAPP

https://faq.whatsapp.com/it/iphone/23559013/?lang=en