Have a short dry run and technical testing a few days before the actual training.
Trainers should familiarize themselves with how the Zoom platform works—how to record the meeting, how to share screens, how to create breakout rooms, polls, etc.
The trainers should also test that their audio and video are working fine.
Participants may be invited to the dry run in order to test their audio, video, etc.
You can also use the dry run and technical test meeting to help participants troubleshoot their machines if they are having trouble installing and running QGIS, downloading the data, etc.