Pedas is popular Mexican slang for 'drunken parties' or 'drinking sessions'. It comes from the word pedo, which literally means 'fart' but has dozens of slang meanings in Mexico.
In the song, the narrator is drinking to forget a lost love, and he says he only talks about her 'en todas mis pedas' (at all my drinking parties). Learning slang like this is a great way to understand the real culture and emotion behind the music.
This song is the ultimate anthem for when you're heartbroken and have zero interest in moving on. Gera MX and Christian Nodal are drinking "Botella tras botella" (Bottle after bottle) to forget an ex, but it's not working. In fact, he admits he doesn't even want it to work: "Pa' ser sinceros, yo ni quiero" (To be honest, I don't even want to). His friends are completely fed up with him, telling him "güey, ya la tienes que superar" (dude, you have to get over her now), but he just keeps drinking and thinking about her.
He knows he messed things up, admitting he was a "mal partido" (a bad match) and that he keeps making it worse by drunk-dialing her. The whole mood is a mix of sadness and stubbornness. He's so stuck that he says he even wrote her a whole CD. The song ends with a piece of advice for everyone listening: "Y si amas a alguien, no la dejes ir" (And if you love someone, don't let them go), so you don't end up having to write a song like this one.