Hecha pa' mí is the heart and soul of this romantic hit, and it's a perfect example of real-world, spoken Spanish. It means 'made for me', but the key is the word pa', a common contraction of para (for) that you'll hear constantly in music and conversation.
By saying 'tú estás hecha pa' mí', the singer declares that his partner is his perfect match, as if she were custom-designed for him by fate. It's a phrase that's both sweet and authentically colloquial.
This song is a super sweet and direct declaration of love. The singer has found the person he believes is his soulmate and he's not holding back. He starts by thanking his partner's parents, saying, "Quiero darle las gracias a tu mamá y a tu papá / Por darle la vida al amor de mi vida" [I want to thank your mom and your dad / For giving life to the love of my life]. He feels they are a perfect match, as if made for each other, asking, "¿dónde andabas perdida?" [where have you been lost?].
He sees his partner as the embodiment of love itself, claiming, "Al amor y a ti los conocí el mismo día" [I met love and you on the same day]. While he admits he's not perfect, he promises to try his best for her and to protect her forever. It's a song about feeling incredibly lucky and grateful to have found the one person who feels like they were custom-made just for you.