Need Help: I am new Android user! !!

[6mackenzie4]

Hi I got an S4 passed onto moi.
Is there a way I can safely restore it to factory settings (just as officially from Samsung)?
I ask this because when I try to update software, this error shows "Your device has been modified. Software updates are not available".
I tried to find a quick fix, but very confused.
I read some stuff on here like Odin, Kies etc; and 'rooting'(is that the Android version of jailbreaking?)
I have no SD card mounted and my Device Status says Custom.
I already did Factory data reset via Settings

I would like a condensed version of steps on how I can restore my S4 to mint condition safely.
I don't know which other info you folks might need so...Please assist!

 

[djdonnyk]

Here you go. Hold down power button, menu key and volume up with device powered off. Once the device starts to power up release all buttons. Follow the screen instructions to wipe device back to factory settings.

Posted via the Android Central App