Alissa G. answered 09/16/20
English & Spanish Language Lover-Grammar Geek-Word Nerd
I agree with Cristian that it's mainly the subjunctive mood being highlighted in this song. However, I'd say that it's not only uncertainty/doubt about whether these things will happen that gives the need for the subjunctive, but rather the desire, wish, or will (voluntad) for them to occur that truly necessitates the subjunctive.
For example:
Que si me muero, sea de amor = If I die, let it be of love - in other words, I wish/desire/will that love be the cause of my death. In fact, this use of the word "be" is actually the subjunctive in English! So you can see that we do have the subjunctive in English, but it's harder to detect since we don't have a distinct conjugation for it the way Spanish does. This is why many native English speakers struggle to understand the subjunctive mood when learning Spanish. We don't realize that we also have the subjunctive in our own language, because our English grammar structure is much simpler and less defined than Spanish is.
I hope this also helps.