Garrote most commonly translates to "tourniquet," a medical device used to stop severe bleeding. It's a very specific and dramatic word that you don't find in songs every day.
In "Hola Señorita," this word is used as a powerful metaphor. After singing, "J'ai perdu beaucoup de sang" (I've lost a lot of blood), the artist follows with, "Il serait temps d'me faire un garrot" (It's about time I made myself a tourniquet). He's not talking about a physical injury, but rather the emotional pain from past relationships, and the need to stop the heartache. This intense, poetic use makes garrote a truly memorable word.
This song is a fun, international flirtation between Colombian star Maluma and French artist Maître Gims, both trying to get the attention of the same mysterious woman. They've heard rumors that her name is María, and Maluma admits he fell for her instantly: "¿Quién diría que me enamoraría, aquel día?" (Who would've thought I'd fall in love that day?). He's completely taken by her elegance, from her designer perfume to the fact that she speaks French. He's ready to stop playing games and get serious, asking her to stop sending mixed signals like devil emojis and instead "vámonos directo al grano" (let's get straight to the point).
Maître Gims offers a different perspective. He's also fascinated by this woman, but he sees her as elusive and hard to pin down, someone who will "apparaître et disparaître comme un ninja" (appear and disappear like a ninja). He knows she's heard things about him and is wary. While Maluma is pushing for clarity, Maître Gims seems more resigned to her mysterious nature, even wishing good luck to whoever ends up marrying her. The song is a playful back-and-forth about trying to understand a captivating woman who keeps them both guessing.