Hope you've got some survival gear with you. Also maybe inside you,not sure if they are a cyborg, a robot or what.
Xerian's a robot. As to whether he's got compartments to store things in his body, that's an excellent question.
Not sure what is powering him, hopefully something that last a long time, probably nothing nuclear though.
As an open species, Synths are highly customisable. However, with Xerian I'm following the base canon fairly closely. So a lot of questions about his anatomy can be answered here: https://synthspecies.com/