Desce do muro literally translates to "get off the wall" or "descend from the wall." However, in Brazilian Portuguese, it's a very common idiomatic expression that means "get off the fence" or "make up your mind."
In this song, Michel Teló is frustrated with someone who is playing hard to get and can't decide if they want a serious relationship or not. He's urging them to stop being indecisive and commit, making this phrase central to the song's theme and a fun, useful idiom to learn.
Michel Teló's "Desce do Muro" is a fun, upbeat plea for someone to stop playing games and commit to a relationship! He's clearly a bit frustrated with this person's hot-and-cold behavior, saying, "Primeiro me dá mole, depois faz jogo duro" [First you're easy on me, then you play hard to get].
He's ready for something real, not just a fling, and he wants them to "Desce do muro" [Get off the fence]! He asks, "Tá com medo de que?" [What are you afraid of?] and reassures them, "Eu não trato mal quem gosta de mim" [I don't treat badly those who like me]. It's a straightforward, charming request to let love happen and stop overthinking it!