Taking Information From Textbox From One Workbook And Entering It In Another

I have 2 separate workbooks that are linked together and work in tandem. One is the Master Workbook "Master Business Plan Worksheet For Sale.xlsm" and the other is the one containing all the Menu Items for the business "Menu Items Workbook.xlsm"

I have a Master Recipe Sheet that I created in the Master Workbook and made sure it all works. Now I have copied it to the Menu Items workbook and copied all the Userforms and created Macros for it but I need setting up the references to the other sheet. I have included the code from the first sheet for you to look over. The textboxes all need to populate to the Master Workbook and all the info for the combo boxes are also in the Master Workbook.

Code:

Private Sub UserForm_Initialize()
'Populate Measurement combo box.
Dim rngMeasurement As Range
Dim ws As Worksheet

Set ws = Worksheets("Start Here Sheet")

For Each rngMeasurement In ws.Range("Sizes_List")

[Code] .....