How to access list' object data deep in a subitem's properties

var List = IR.GetPopup("Popup1").GetItem("List 1");

List.GetItem(item, 3, {Text:})

says it contains a null, but shouldn't this work? I'm not familiar with which method 'Gets' the data for use as a variable. I'm trying to copy a list item and all the property values that are not kept in the initial creation if a template, from a button within a list item (ie the text values in all the subitems).

This doesn't work either but might clarify what I'm trying to do:

var NeedThisTxt = List.GetItem(item).GetItem(subitem).Text;

//so I can do the below

List.CreateItem(item+1, subitem, {NeedThisTxt});

Please and Thank you!