There are two options for printing different labels on the same page.  One is to use an External Data Source.  This is where all the information is in a file such as an Excel spreadsheet or a text file.  The Help file in Labeler has detailed instructions on how to implement this.  Go to Help>Contents>Reference Guide>Menu Commands>Data.  

The second option is to use the Prompt at Print Time option.  This allows the user to change Bar Code objects, Text objects and Picture objects before the label prints.  The Help documentation has information about this under Help>Contents>Reference Guide>Menu Commands>Format>Prompt at Print Time.