How can I present different fixation time?

I would like to present the fixation time randomly to the participants from
1000ms to 2000ms in 100ms.

ex) cue time of 1000ms, 1600ms, 1300ms, 2000ms 1900ms and so on)

I have tried using the “time limit-level trial” but it doesn’t work.

How can I do this?

Thanks in advance

Using a trial variable of type Time Limit is the correct approach. After you have created it, you need to tell the event (in the Event Editor’s Input tab) to use it. Did you do that part also?