Can you be more specific?
Are you attempting to take fields in Microsoft Excel (and what version) that contain values like 1, 2, 3, etc. and convert them to numerals like I, II, III, etc.?
You have the ability to change or standardize the data type in each cell.
Select the group of cells you want, right click, and select Format Cells. On the first tab, choose custom, and create the data type you want.
Hope this helps!