Ok ... my mistake.

In your first Word .docm ... in the "ThisDocument" paste "

Option Explicit

Private Sub CommandButton1_Click()
    RunMacroInSecondDocument
End Sub

Then in a regular module paste :

Sub RunMacroInSecondDocument()
    Dim wdApp As Object
    Dim wdDoc As Object
    
    ' Open the second Word document
    Set wdApp = CreateObject("Word.Application")
    Set wdDoc = wdApp.Documents.Open("C:\Users\logit\OneDrive\Desktop\Doc2.docm")
    
    ' Run the macro in the second Word document
    wdApp.Run "hellow"
    
    ' Close the second Word document
    wdDoc.Close False
    wdApp.Quit
    Set wdDoc = Nothing
    Set wdApp = Nothing
End Sub
[/CODE]

Note ... for testing purposes my second Word document is named Doc2.docm . You'll adjust the name in the macro for your own purposes.