Steps to root Unite 2 Kitkat:
Step 1: Copy downloaded zip file to External SD card.
Step 2: Reboot phone to recovery. (To open recovery mode first switch off phone then press and hold all hardware buttons i.e. vol up + vol down + power button. Then two options will show in screen. Press vol up to reboot to recovery)
Step 3: Press vol down to select install zip from sdcard then press power button to confirm
Step 4: Select choose zip from sdcard and press power button
Step 5: Select downloaded file superuser.zip or kinguser.zip from list of files and press power button
Step 6: Select Yes – Install superuser.zip and press power button. Now wait for rooting to complete. If it shows installation aborted message then either zip file is corrupt or you are using stock recovery instead of custom recovery. See requirements section above.
If rooting completes successfully then you’ll see message Install from sdcard complete
Step 7: Reboot phone after successful installation.
Now install root checker app from play store to check phone is rooted or not.