Firstly you will need to login to the unit , go to System -> Digital -> Channel type, then select the configuaration that supporst IP. An IP camera is then connected to this unit via it's RJ45 (lan port) using a network switch or POE switch.
what is maximum storage this unit can be expanded to?
Has this got a side cable exit point on the bracket?
No it does not have this feature.
does this unit support ptz
Yes this unit does support PTZ telemetry control via RS485 or UTP