Ok, I'll assume that you're very young. There's a number of problems I see with your knife and it's purpose.
#1- It's very big, and I say that as someone who digs big knives. Do you know if there's a legal blade length limit for what you can carry where you live? You'd better find out or you could get yourself into a legal jam that would haunt you the rest of your life. Even if it is legal to carry, how are you going to carry something that size?
#2- The design kinda leaves something to be desired. Making deep cuts into a knife's edge doesn't make a saw. Real saw teeth are set out wider than the blade so they open a channel wider than the saw blade. Those teeth are narrower than the rest of the blade so it won't make a wide enough channel to act as a saw. If you try to slice with it like a normal knife blade, those teeth will snag and stop instead of cutting. If you try to chop with it, the teeth are likely to bend or break. Basically, all they'll accomplish is make it so it can't really do anything well.
#3- Knives are generally poor choices for self defense. You have to get close to use a knife, aside from the obvious risks that presents, it might make legal problems more likely if you ever have to use it. Also, if you don't have training in some kind of knife fighting technique, you're just going to be flailing wildly. Something that heavy will be even more difficult to control. You'll be almost as much danger to yourself and bystanders as to an opponent. If you're determined to use a knife for self defense, get the training and that will dictate what sort of knife you should carry.
Sorry to wizz in your Wheaties, but that's how I see it.