My boss's skype number is forwarding to my cellphone number... and I just want to know if it's possible for him to record any calls coming through? So lets say someone call the number, and I answer it after redirecting to my phone... can he be recording that call on skype from his end? Or is the only possible way for calls to be recorded for it to be done on the cellphone it's redirecting to?

Depending on his level of software, and how he is forwarding it, yes it could be done, but it is not common, and/or he can require you to record them.

These are his calls, not yours, and how you respond to calls to his phone, is part of the job.