[Q] Reinstall in MediaTek GT-I9190 Mtk6572 the operating system Android 4.2. topic

Hi, I accidentally erased Android system files on my phone and it stopped working. I have a Chinese replica of the Samsung Galaxy S4 mini mobile device. My cell phone was manufactured by Mediatek. MTK6572 GT-I9190 with entrance to a single SIM card. I would return it to factory mode with android 4.2. One would, if possible, teach me how to reinstall the android 4.2 operating system and send me the files needed for this?