I have followed this tutorial and I chose option 2 to
"Just download nethunter and NH terminal app from nethunter store and install them. Then download nethunter generic zip from nethunter download page and extract it. You’ll get a zip file with the chroot. Copy that file to the root of sdcard. Then open nethunter app and goto install page and select install from sdcard. If it says file not found, then rename the file to the exact name it searches for and it will install. It will take some minutes to install. After installing, you can start the chroot. That's it."
I downloaded both the nethuntergeneric.zip and the nethunteroneplus3any10kernel.zip
in either i cant find chroot.zip only installchroot.sh is that what I need?
Edit:
I figured it out. The file mentioned above is a file called kalifs-arm64-full.tar.xz
I had to rename it to kalifs-backup.tar.xz and save it to root of emulated/0/ then I installed by pressing kali chroot manager and install from storage. My location was was emulated/0/ as this Oneplus3 doesn't have an sd slot but for other phones the location ends in /SDCard/