SSIS Foreach Loop export to same file

I am trying to export 2 files (customers and orders) from two different tables. The tables will change constantly and I will have to export data that has both customer and order records. Also, I will have to update the records that I exported at the end of the run. I am thinking about creating a SQL Execute Task and store the ID in a full result set and use foreach loop to export the IDs that are in Full Result Set and at the end update them to “Exported”. But I’m having problem exporting the data in the same file and I also want column name to be in the first row. Is there a way I can achieve this? Thanks.