Support for Visual Basic for Applications (VBA) for ArcMap and ArcCatalog ended with the ArcGIS 10.2.2 release, and Esri has not included VBA compatibility setups since version 10.5. See: ArcGIS Desktop and VBA Moving Forward
Instructions provided describe the steps to create a new UIButtonControl in ArcMap.
Select Tools > Customize to open the Customize dialog box.
Click the Commands tab.
Select UIControls from the Categories list box.
Select Untitled from the Save In dropdown list to save the button to this map document. Select Normal to save the button to all ArcMap documents on the machine.
Click New UIControl.
Select UIButtonControl and Create.
Drag the new UIButtonControl to the toolbar of choice.