When you say data 1, data 2, data 3... are you referring to rows or columns in your portal? (They read like you are describing columns ( Fields ) when you really should have rows here for a more flexible control of your related records in the portal.)
Import Records will do the job, the trick is to perform a find or other operation that pulls up a found set or just the records you want imported to the other file, then use Import Records to import this found set. Import Records has a lot of options and can result in major changes to the records in your database, so make backups just before doing this until you are confident it is working correctly.
On another note, why are you copying records from one table to another? Often, new users attempt this approach to managing their data when a simpler approach that keeps all the records in their original tables will work better. Thus, it's possible that theres a better approach available here.