How can I make a data comparison video for YouTube?

Everything here look# like conventional animation techniques with one exception.  To get the scrolling, I'd create a super wide comp, animate each element then nest that comp into a regular sized one and animate its position. 
Over time you'll pick up techniques to speed up your workflow, but they can be more confusing when you're getting started.

These are just conventional AE techniques. Nothing special. Start learning AE by reading the online help and watching tutorials.

After Effects User Guide

Mylenium