"Como la flor" (Like the flower) is a love song about letting go, and here Q' Lokura and Valentino Merlo sing it live, trading lines in front of a cheering crowd. The singer compares a love to a flower: "Como la flor, con tanto amor, me diste tú, se marchitó" (Like the flower you gave me with so much love, it wilted). The love has dried up, so he is leaving: "Me marcho hoy, yo sé perder" (I'm leaving today, I know how to lose). That line is the heart of it. He is not begging or blaming, he is taking the loss with dignity, even if it stings: "Ay, cómo me duele" (Oh, how it hurts).
What makes it sweet rather than bitter is the generosity: "Sin embargo, te deseo lo mejor" (Even so, I wish you the best) and "Si en mí no encontraste felicidad, tal vez alguien más te la dará" (If you didn't find happiness in me, maybe someone else will give it to you). The second verse turns more personal, "Con tu adiós, te llevas mi corazón" (With your goodbye, you take my heart with you). Stay for the end, where the music stops and the two singers thank each other on stage. Valentino calls the night "cumpliendo un sueño" (making a dream come true) and his partner "este crack" (this ace), Argentine and Spanish slang for someone brilliant at what they do.
Learner tip: "Yo sé perder" uses saber + infinitive to mean "know how to", a pattern you will hear everywhere.