This is something you'll need to setup yourself. The NET.HTTP object provides functionality for making raw HTTP Requests.  It's a matter of setting the request parameters to match the Rest API.

You can call the Rest API from the NET.HTTP object.

If the old form is a regular AcroForm, then you should not have created the new form as a LiveCycle form. LiveCycle has a very different way of handling data, so the data files are not directly compatible. I would highly recommend that you re-create the form again, but this time as a regular AcroFor...

Yes, you'll find part of your answer in this article:https://acrobatusers.com/tutorials/change_another_field The article presents a technique for setting the value of other fields from a dropdown. But you can use this same technique to show/hide other fields using the "field.hidden" property.

Why can't you use the "Goto page view"?  This is the preferred method because it will work when JS is not available. Just open the attachment in another Acrobat tab and when you select the "Goto page view" action, click on the embedded file.The JavaScript for this is tricky, but here it is:var oDoc ...

If this "SubForm" is a completely different file, then the best way to distribute it is to make it an Attachment to the other file and then use the "GoTo Page View" action on a Button to open it.  There's also a JavaScript function for this.You could also put it on a server and have the button open ...

The idea is to create a page that is basically a table of extra fields.  You make this page a template and set it to hidden. Then you "spawn" this template into a new page from a script. Typically this is done from a script on a button labeled something like "Add More Entries". In addition, you coul...

I believe your colleague was referring to LiveCycle Forms. A technology still supported by Adobe, but one that most consider dead.It is possible to use Page Templates on regular PDF forms to create new pages. There are other methods, but this is the only reasonable way to dynamically create fields.

The code I posted for the button click has nothing to do with making the check box invisible when the PDF is opened, it is only intended for the button. The visibility on open is a completely different issue. If you set the check box presence to "invisible"  in LC Designer, then you open the PDF and...

I prefer JavaScirpt because it is useful in many other places. That and LiveCycle is dead.Were there any  error messages when you ran this code?You should concentrate only on the Visible case, cause anything else is invisible.if (adminPass == "123") then  occ1.pesence = "visible"else  occ1.pesence =...