You can use OOTB activity MSOGenerateExcelFile. Call this activity keeping your pagelist (or data page ) as step page. It takes three parameters,
1. FSFileName - Name of the excel created,
2. TemplateRFB - Template name (format : "excel!TemplateName!xlsx") ,
3. DownLoadFile - true/false.
Prior to using this activity, create a template excel file and define the column header and property reference for column value. Create a binary file in PRPC and upload this excel. This template excel will have the details of the properties you want to send to the output excel and its name is required for the second parameter(pass the file name along with the extension here).
The main difference between these two file extensions is that the XLS is created on the version of Excel prior to 2007 while XLSX is created on the version of Excel 2007 and onward. They are also different on the basis of information storing way. XLS is a binary format while that XLSX is Open XML format.