How can i avoid the kill switch?

I have my old Nvidia shield tablet and i have WiFi off and powered off.

I've been reading you can stop the kill switch from i guess changing the boot loader or operating system?

I new to this stuff.

Could someone just give me some directions on how to go threw this process please.

I don't know if it's to late cause i have the most recent update? but like i said it's turned off and WiFi is off and i heard that the kill switch is sent over the internet to your device and you don't have to confirm it.
So i hope my system is safe until i can do what ever you guys advise me to do.

Thank you...