But I do not know how to read a file stored on a SD card binary ?
All of the data stored on an SD card is in binary. It is the interpretation of the binary data that makes the difference.
Suppose that you read byte from a file on the SD card
The same byte might be interpreted as 65 in decimal, 41 in Hex, 'A' as a character, 01000001 in binary or even as 101 in octal
Summary : read a byte and interpret as you wish.