Welcome!
First off, great advice from the people above. Indeed, you don't need pro-equipment off the bat. I just like to make my vacation vids and weekend events more interesting and don't really need to buy a $3000 camera. But it is indeed addictive and you start drooling over the nice stuff.
A few pointers:
Watch reality based programs or documentaries for ideas on camera angles, framing, and length of scenes. Movies are also good, but as previously mentioned, they have large budgets, pro equipment, and scripts - you don't.
Film like crazy. The more footage you have, the more you can accomplish in editing. Shot lists are helpful for when you can't go back and re-shoot.
Practise holding the camera steady, pan slowly, and walking with the camera. Jerky movements make it hard to watch.
Always let the camera run for an additional 3-5 seconds to allow conversations to finish and transitions to have room.
Tripods, even cheap and mini tripods, let's you include yourself in the shot if no one else is around. I always bring my mini tripod with me.
Always mark tapes, and never record over a tape (unless it's just practise footage). All hard drives will eventually crash, so save the originals.
Have fun and don't forget to capture some everyday stuff: an average day in high school at age 15 is a riot to watch when you're 30! Trust me, I was fortunate enough to have some fun footage from early college almost 15 years ago, and it is priceless to watch!
Anyway, this is a good forum with very knoledgeable people. Enjoy.