Hello @AhmedHaggag,
It is in fact possible to send/receive CAN frames from Linux in the RDB3 board. Can you confirm if you checked section 12 LLCE Support specifically subsection 12.3 CAN of the BSP38 user manual? [page 101, 102, Linux BSP 38.0 User Manual for S32G3 platforms].
There you can find how to use some can-utils commands. Therefore is not mandatory to build an M7 image to use the CAN peripherals, Although it is highly recommended to drive the CAN modules from the M7 cores in critical applications.
We don't have any example on how to create a Linux C++ application to execute the can-utils commands. One suggestion could be to use the standard C library function popen, to execute terminal commands in your own programs.
For more information about the LLCE module you can check the following documents:
S32G-LLCE-STD-PB
S32G-LLCE-FDK-PB
Let me know if this information was useful,
Best regards