i don't get it after months of playing songs i don't usually choose the songs that you need to mute so i didn't really learn how to mute.

i was wondering how do you mute i'm a right hander playing an acoustic guitar and do you mute with your right hand or left? because it seems hard to strum and mute at the same time with your right hand.
i use my right hand mainly. put your hand like at the end of the bridge just enough to change the sound

it takes practice to pick and mute at the same time
Yeah man, you mainly mute with the heel of your right (picking) hand, the part just near your wrist.
it's a combination of both really, depends on the song you're playing and the genre/style, learn both
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Make a "karate chop" shape with your right hand parallel to the bridge and rest it there. Practice that to get the sound you are looking for. Pick with more wrist than forearm.
So it goes.