It's really going to depend on what you want to do with it. Assuming the config isn't left over on the device from the prior owner, a bare Layer 2 switch with PoE might at most require you to turn on PoE. If you want to run VLANs, that's doable as well, though your best guide as always with networking gear is "?" and "Tab" to find autocompletions and various options at any "level" of a command.
I would start with "show inline power" and make sure "admin state" is on. If it's off, you can either turn it on for specific ports:
Code:
config t
ethe 1/1/4
inline power
Or just turn it on for all ports (in which case replace 1/1/4 above with "1/1/1 to 1/1/48").
VLANs is another topic altogether, but if you know any Cisco, understand that the Cisco method (config t > interface blah > vlan X) is not the way Brocades work. They're kind of the opposite, where you go config t > vlan X > untagged ethe blah (or tagged ethe blah if you want a trunk/tagged port).