Or you could embed some code in an Excel spreadsheet and (maybe) use this blank worksheet as a template.
The SSIS process populates the spreadsheet template with data and when the user opens it they can click on the 'Format' button and the pre-written code executes to tidy things up as required. Or you could make it auto-execute.
The benefit of this approach is the avoidance of the need to install Excel components on your SSIS server.
If you haven't even tried to resolve your issue, please don't expect the hard-working volunteers here to waste their time providing links to answers which you could easily have found yourself.