I am guessing you mean how to obtain the input/output data required in the first step of the PID Tuner.
If that is the case, then you need to find where the PID code is executed (if is a PLC then find the PID block). Then record:
The output of the PID block is what the PID Tuner needs for the input column.
The input of the PID block (which is the process measurement) is what the PID Tuner needs for the output column.
The time of the experiment.
As you see input and output are inverted between the PID block and what the Tuner expects.
Now to obtain the experiment data : With the PID block turned off, execute an experiment by making a manual step change on the PID output (what would be the Tuner input) and record all the data of that experiment. If you can make more steps, the better. Try steps up and down if possible. Then load that data into the PID Tuner.
Once you load that data, save your project and share your link here, so I can further assist you.