Hello @jhChoi ,
You need to call l_u8_wr_ macros to write the data that you can get in lin_cfg.h file according to your LDF.
I have attached LIN User Manual. Check page no 53 you will get the sample program it might help for you.
The same document you can get in your location C:\NXP\LIN_stack_S12_4_6_3\Documentation if you installed LIN stack.