I've looked around and couldn't find this posted anywhere, but here in my issue:
When I put an audio (.mp3) fine on my timeline, nothing was happening, so I looked it up, and apparently you need to hit the "RAM preview" button in the preview panel to render it out. I watched a few tutorials, and it seems like they would hit the ram preview button, it would render out, and then it would work. When I try doing that, it simply just plays the track, and says "playing from ram" in the info panel. What can I do differently to be able to start and stop the audio from the timeline? Thank you in advance!
Read up on RAM and audio previews in the help files, don't rely on vague info from badly done tutorials.
You're facing a real paradigm shift. It sounds like you expected AE to behave like a video editing application.... well, it doesn't. It's a different kind of video tool, with its own ways of working. To new people, it may not make sense.
So if you're new, do yourself a BIG favor and learn about the AE Basics, which everyone has to have:
Once you have the basics, life gets a lot easier.
Oh, there's this too: I wouldn't use mp3's in AE. I'd convert them to an uncompressed file like wav or aiff. AE's been known to have occasional, hit-and-miss problems with compressed audio. It's just too darned easy to do that it doesn't make sense NOT to do it.