Double-click on the tFileOutputMSXML component to
open the dedicated interface or click on the three-dot button on the Basic settings vertical tab of the Component tab.

To the left of the mapping interface, under Linker
source, the drop-down list includes all the input schemas that should
be added to the multi-schema output XML file (only if more than one
input flow is connected to the tFileOutputMSXML
component).

And under Schema List, are listed all columns
retrieved from the input data flow in selection.

To the right of the interface, are expected all XML structures you want to create
in the output XML file.

You can create manually or easily import the XML structures. Then map the input
schema columns onto each element of the XML tree, respectively for each of the input
schemas in selection under Linker source.