VBA for Word

tab press event.bas

Option Explicit
Dim myKey
'   https://learn.microsoft.com/en-us/office/vba/api/word.keybindings.add

Private Sub Document_New()
    KeyBindings_AddKey
End Sub

Private Sub Document_Open()
    KeyBindings_AddKey
End Sub
 
Sub KeyBindings_AddKey()
    CustomizationContext = ThisDocument
    Set myKey = KeyBindings.Add( _
        KeyCode:=BuildKeyCode(wdKeyTab), _
        KeyCategory:=wdKeyCategoryCommand, _
        Command:="TestKeyBindings" _
    )
End Sub

Sub KeyBindings_Clear()
    CustomizationContext = ThisDocument
    myKey.Clear
End Sub
 
Sub TestKeyBindings()
    MsgBox "Hello, world!", vbInformation, "KeyBindings Test"
End Sub