I have a Android device and a 64 GB SD card. I also have an image of Kali Linux on my phone. I don't have a laptop or computer. How do I flash the image to the SD card via my phone.
I would prefer not to root my phone. But I can if you want.
You'll need to install disk tools on your Android device. The most popular toolkit for this purpose is Busybox.
Keep in mind that low-level filesystem access that you need to flash an SD card requires a rooted phone. There are busybox releases which can be installed without rooting, but those won't help you with your task.