excel spreadsheet with drop downs

Excel uses something called "data validation" to create those drop down lists. Numbers has a cell type called a "pop up menu". Numbers does not import data valuation or export pop ups.

Data validation requires a list of the allowed values in Excel. In some table somewhere should be that list of values (I don't think you can create a data validation list in Excel any other way but I could be wrong). In Numbers, select all those cells and change the cell type to pop up menu. After converting all those cells to pop up menus, select one of them, Copy, Paste to wherever you need that "dropdown" list.

You can use a table range as the source.

You can also use formulas to create dynamic drop downs that change depending on values in other cells, or auto extend to supply only the proper range of cells.

If the excel file being brought over has one of those, there is no way to duplicate this behavior in Numbers.

The only kind that can be recreated in numbers is the hard entered static values.

Jason