You do not have to download Zoom If you download Zoom you will have more tools and settings to use
The tips are for those with Zoom downloaded: You have the ability to mute yourself
You have the ability to "STOP VIDEO" (you do not have a transmit a video) When you are in a meeting you can view it "gallery" style or "speaker" style "Gallery View" allows you to see the other participants in a grid like fashion "Speaker View" allows you to see the person that is speaking If taking an online class you set your device to "speaker view" so you can see the instructor better
You can adjust the volume of BOTH your microphone AND the speakers separately in the audio settings