To download the app onto your computer go to: https://zoom.us/download#client_4meeting
To download the app on your iPhone or iPad go to: https://apps.apple.com/us/app/id546505307
To download the app on your Android device go to: https://play.google.com/store/apps/details?id=us.zoom.videomeetings
To add the app to your Chromebook: https://chrome.google.com/webstore/detail/zoom/hmbjbjdpkobdjplfobhljndfdfdipjhg?hl=en
Your teacher will send you links to Zoom meetings, when you click the link it will launch the app and you'll be connected to your class.
We hope this helps!