Help with data entry to field list to affect two tables

Good morning.
Just a week ago I started with Buuble in order to make an application for the control of a laundry, where an employee has to register the orders of customers who bring their clothes to wash.

This is the structure of what I have to do.
2022-02-25 08_58_54-Estructura datos - PowerPoint

My problem is that I am not knowing how to properly register the products inside the note (a note has many products) and then register the order number to the customer (a customer has many orders).

My process is that first I enter the order data: Order number, customer number, this is where I enter the order number. Then I need to enter the product data by selecting it from the catalog. Here is where I start to have problems because I don’t know how I can add the products to the same order, I understand that it should be with the instruction make changes to. But how to register all the products that must be in the order and then add them in the note is where I am lost, can I register everything that appears in a repeat group or does it have to be one by one?

If you can give me an example to better understand how this works or some advice, I would appreciate it.
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