Ok what I want to do is make a drop down menu with the same values that they
input in a different worksheet. However i dont want there to be duplicates in
the drop down list if they put the same value in twice.

Im going to have a userform made with a drop down list for the values they
input in a previous worksheet and another field called miles that they put in
themselves. When they click on commandbutton1 it will input those fields into
A2 and B2 then will clear the userform to input again. If they push
commandbutton2 it will end the macro.

Inputworksheet: Miles
Worksheet with values for dropdown: Expense (Column H)