How to switch to silent/mute mode using volume keys. If I press volume down button it is going to vibration mode only... please helpIn almost all phones if we long press volume down key then it goes to silent mode but not in Samsung phones

Please see the attached screenshot. I have highlighted green graph so depending on the Green Part may I know how much time it took for the last full charging?

I'm using S20+ and I observe that Microphone range is very less than a 1 meter. When I turn on Loudspeaker during calls, other person says my voice is very low.Is this my device problem or it's the way all S20+ devices have??