First see if you can establish communications with the power suppy using Meas and Automation explorer (MAX for short). If you can find your GPIB card in the directory tree choose it and then use the scan for instruments tool. If it can see your power supply it will give you it's address. Choose it and try the Communicate with my instrument tool. It will send a IDN? command to that address and it might return a string if the instrument understands the command. If not you will need to dig through the power supply manual to find the correct commands.
Now Using LabVIEW 2019SP1 and TestStand 2019