Why open raw file only shows FP? The raw data is in pl2 format, in which WB, FP and SPKC are recorded. How can I analyze the SPKC data in it?
It is the first time to use brainstorm, and there are some basic questions that I hope can be answered. 
You can edit the channel file to classify the channels by types in the way you want:
https://neuroimage.usc.edu/brainstorm/Tutorials/ChannelFile#Edit_the_channel_file
We recommend you start by reading all the introduction tutorials + the EEG/Epilepsy tutorial using the example datasets provided before trying to process your own recordings.
https://neuroimage.usc.edu/brainstorm/Tutorials