This first section of videos should provide you with all that you need to get started with using Zoom with your students.
This second section of videos could be used to share with your students, to explain to them how they join a meeting as well as navigate the controls.
Here are some extra Zoom tutorial videos that could help you further when using Zoom with your students
This feature allows for the group to initially meet as one like in any face to face classroom. Then break out into a series of groups to work on specific task or a generic task to then return to one who group.
Useful Zoom reading....