Sending Updates/Additional Info to Colleges

How are you supposed to send additional information and updates to college about extracurriculars or awards or just information in general? (Assuming you’ve ALREADY submitted your app)

I asked my college, and they told me to send through email in a document.

That’s what I did, but how exactly is the information on that document viewed?

Do they see it as is or do they makes notes of it or what?