I've seen solutions on line but just don't understand.
A combo list can show as many columns (which usually refer to table or query fields) as you want but the control can only show a value from one column without concatenating multiple columns into one. In effect, that's still only one column - a single column of concatenated values from other fields. I figured I'd better elaborate on that or I'd get some disagreement. Also, the control can only be bound to one field and is a 1 based collection. Column(0) is available, but I rarely use it because it provides the list row index of the selected record.
Bound column is set to 1. when i change to 2,
This sounds like you are showing the ID column, which is usually not done. While the ID is often part of a combo, listbox, query etc. it's typically never shown to the user in order to avoid confusion and questions about it. In order to bind a combo selection of "Smith" to ID 55, the ID is the first field in the query or record set, it's column width is set to 0 so as to hide it, and the bound column is set to 1. The order of list columns will match the order of the query fields.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.