You buy bicycle brake cables, either from a bicycle store, or from an internet source. If you need to be told this you probably need to be told how to install them as well, so go look at www.bicycletutor.com, www.parktool.com or www.sheldonbrown.com
most bmx bikes dont have front brakes now ans if you pedal backward and it has pedal brakes its not a bmx bike
BMX
No. Some more intended as child's bikes are fitted with coaster brakes.
its good for the price and the frame is strong but the brakes are weak
Clean rims, good pads, nice and smooth cable runs.
Yes, because as an bmx rider i aslo do trick ridding and we do need pedal brakes
That's a pretty muddled question, you might as well ask what makes shoes different from other shoes. BMX bikes can be built for different uses, there are race bikes that are light and have brakes, there are vert/trick bikes that don't have brakes and can take a lot of abuse.
Well, if you ever intend to ride it on the streets, it should have brakes.
Then it's probably intended for vert/flatland or some other form of trick riding where brakes generally aren't used. Depending on if it has a brake bridge in place or not it might be possible to drill it for brakes. You won't have any cable stops so you'll have to run full cable sheaths all the way from the levers. If you want to ride it in traffic or race it you might be better off selling it/trading it for another bike.
It depends if you have a 3 piece crank, spokes, brakes.
Hand brakes are attached to the rear brakes in most vehicles. Start with making sure the rear brakes are in good working order and adjusted. Most vehicles will have a cable adjustment connected with the front cable that leads to the hand brake. Make this cable adjustment after the rear brakes have been inspected and adjusted.
BMX isn't a manufacturer, it's type of bicycle - just like sneaker is a type of shoe. BMX doesn't make any bicycles. Bicycle manufacturers make BMX bikes. And pedal brakes aren't that good on a performance bike, as you have to wait until your pedals are in the right position before you can brake. But it's possible that you can find a BMX-looking kids/juvenile bike with a pedal brake. Don't expect it to do particularly well if it gets ridden hard though.