I don't really know what you're calling a driver, but it's probably the sprocket and the freewheel mechanism. And yes, it can be removed. You need a special tool, a freewheel puller, and it has to match the make of the freewheel that you have. check out www.parktool.com for more info.
change out the hub
it turns the wheel
No, you can just cut your chain with a chain breaker or just take it to a shop and they will do it for you.
Two, but this is not the same as how many speeds the BMX bike in question has. A BMX bike has a sprocket in the front, and a cog in the back and each is a gear, but is considered a single speed bicycle because two gears and a chain are required for transmission of rotational force from the crankset to the rear wheel.
There are two different hub designs for BMX, freewheels and freehubs. You need to know what you have if you want to replace the sprocket by the rear wheel.
take the cranks off and then take your old sprocket off and then put the new one on and then put the cranks back on.
they can range from 46teeth on a chain wheel all the way down yo a 22tooth chain wheel.
You need the right kind of hub for that. If you haven't, buying a new rear wheel - with the right kind of hub - is probably the sensible option.
The key components of a BMX brake system are the brake lever, brake cable, brake caliper, brake pads, and the braking surface on the wheel rim. When the rider squeezes the brake lever, the cable pulls on the caliper, causing the brake pads to press against the wheel rim. This friction between the brake pads and the wheel rim slows down the rotation of the wheel, ultimately controlling the speed and stopping power of the BMX bike.
When choosing a BMX cassette driver for your bike, consider the number of teeth, material, engagement points, and compatibility with your hub. These features affect the performance, durability, and smoothness of your ride.
Depends on what's keeping it back. If you've got strength left, but can't turn the cranks any faster, get a smaller driver. If you think you could pedal faster but don't have the power, get a bigger driver.
Having one or more spokes loose can cause creaking. If this is the case take you bmx to your local bike shop. Your wheel may not be true (damaged e.g. fractured/not original shape) another reason is that your tire may not be pumped up all the way and the inner tube could be chaffing on the outer casing.