Hey @Robert_Storrs! Welcome in!
Yes, you’re correct.
The first field is the primary field.
Since this it is functionally the identifier for the record, you cannot move the field itself around.
However, that does not mean you cannot move the data.
All you have to do is duplicate the primary field. Be sure to select the option to duplicate the values as well.
Once you have the new field, you may change the primary field to be something else that you prefer and then move the new field to wherever you’d like it to remain.