How come Voy (Spanish) means I? 10 p!?

I think you're misinterpreting something translated with "voy". Voy is the present tense 1st person singular of "ir", it means "I go" or "I'm going". In Spanish, the subject pronoun ("I") is optional and often left out. The form of "voy" tells a spanish-speaker that it's me who is going and not somebody else, without the need of a subject.