Since you already have a Dut board wired to connect each of your device pins to a tester channel, you perform a Curve Trace measurement with ETS2k.  The fundamental principle of curve tracing is to map the relationship of injected input current to measured input voltage (or vice versa) of a target pin, while other pins are either disconnected or connected to ground.   The HiLevel Curve Tracer facilitates all of the above with the provision that only one of the other pins will, at a given time, be held to ground (dedicated ground pins are of course held to ground in all cases). However, within the course of the total test, all other pins - one at a time - may be connected to ground.  Furthermore, power-pins are usually held to ground unless power (in the Curve Trace Window) is un-checked, in which case all power pins will be physically disconnected during the test(s).

Simply specify the test using the three tabs on the Curve Trace Window (found in the FA sidebar).  The easy way to start is with the Pins tab: