i connected sd card at the bottom of raspberry pi 3. But there is no place to put sd adapter? what is it and what it does? Sdcard has a memory of 16G, and i was able to coonect it, bottom of the pi. In case of urgency, how can I shutdown the pi in case of kernel panic, like with PCs.
Assuming you mean something that looks like this . The top item is a micro SD card adapter, and it is used to allow reading and writing of the micro SD card in a computer with only a standard SD card slot. It is not needed by the Pi 3, since the Pi is designed to use a micro SD card.
If the Pi has a kernel panic your only option to shut down may be to pull the power.