Column dependent on first row cell entry

[Rosadocc]

Hello,

I have a table with a column where all rows that will be populated based on the first rows data entry (based on a data validation list). Depending on that entry, all new rows after will have that same entry. Looking for a formula to help me do that.

Header (A1)

1234 (A2 Based on data validation drop down)

123 (A3 based on selection above)

123

<tbody>
</tbody>

 

[Roderick_E]

In A2 something like =a1 then drag down. Need to give more directions to help further.

 

[Rosadocc]

Sorry I shouldve been more specific with what I am trying to do. It wouldve helped if I mentioned a new row is added based on values entered in the column next to it. For example if a value is entered in cell B3, A3 will automatically populate with the value selected in A2's drop down menu.

 

[Rosadocc]

Sorry cant find any other way to explain what im looking for so attaching this image. Any help is appreciated: