"Drivers"?

I have a tablet which can't find the firmware, and trying to develop the mine.
I was reading tutorials and information that find and some well have some questions.

I downloaded a firmware with Android 4.4.2, "installed" and runs good, except that:

• Don't works WiFi


• Don't works Cameras


• Don't have Phone app, i assume that no detect the "3g"

I do not know as they are known the "drivers", are obtained or how are modified.

Upon installation of the firmware, using a computer mechanism, successfully extracted, from the gadget unchanged, with Android 4.4.4, the files:

• boot.img


• bootloader.img


• data.tgz


• recovery.img


• system.img


• system.tgz

Any information that is useful to the case, do not hesitate to ask.
From already thanks and hope, apologize for the lack of appropriate language.