Hello; how can we interface between FileMaker Pro Apps and cash machine from Banks so when making invoice the amount required will be sent to the machine and buyer will need to insert bank card and password then will be authorized.

Thanks

You would need an API and merchant account possibly a plugin to take payments from customers. 

How I get API ?

The API is dependent on the merchant that you use they don't just give it to you. Also you need to have an account and credentials in order to access their services.

 

https://dbservices.com/blog/payment-processing-in-filemaker-using-stripe

https://www.productivecomputing.com/blog/connect-filemaker-to-the-stripe-api/

https://360works.com/credit-card-plugin/

When integrating with a hardware terminal, practically speaking, the only chance you have to integrate is when your merchant services provider has developed and installed some kind of software that allows you to interact with the device.

Many years ago I worked with a merchant services provider in Canada that developed an interface called ECRI that allowed us to send amounts to the terminal through an RS232 serial port, then the device would send back the result after the transaction completes.

These days, my merchant services provider uses a cloud-based solution where in order to initiate a transaction, you make an API call to your merchant services provider, then they communicate with your hardware device to display the amount and prompt to insert the card. When the transaction completes, a webhook fires the result back to your server. Unfortunately it costs almost a thousand dollars to get your app setup & certified.

Stripe has a simple offering, where you communicate directly with the terminal using JavaScript. https://stripe.com/docs/terminal

In summary, you need to ask your merchant services provider what options they support, or switch to a developer friendly provider like Stripe.