Help with Cell reference and updating in VBA

[Zelcombe]

Hello Everyone. I am a little stuck on what is probably a very simple piece of code, but y'all know how it goes when its the end of the day and your brain is mush.

If there is already a post that has an answer similar to what i am looking for please let me know.

Cells and Values for Reference:

Column A	Column B
[Any Real Number]

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</tbody>

Description of what I need to happen:

1. On Workbook open check to see if a cell on a certain sheet has a value if it does exit sub. (This part I know how to do and have set up).
2. If the cell in step number 1 has no value then proceed with the following:
3. Look for the first empty cell in Column B.
4. when it finds the first empty cell in Column B the code grabs the number from Column A and places that number into UserForm Textbox when the Userform is activated.
5. After the code places that number from column A into the Userform the code would then move down one row and add a specified numeric value to the previous cell in Column A.
6. End Sub

Thank you all for your assistance with this.