If I'm applying to multiple universities, do I have to ask my school?
That depends. But, if you can use Common Application Welcome to CommonApp, to all the colleges you apply through them, you just need to request your school once to upload the transcript and that will be commonly accessible by all the colleges you apply, post that transcript is uploaded by the school. If you are sending your application to different colleges, each one of them have their own individual application system, then you need to request your school to send one to every one of them.