perfect pitch - the ability to identify the pitch class of a note without a reference, and/or to produce any pitch class correctly on request (also without a reference) - is the subject of much debate among musicians.
some people believe it’s innate (that you’re born with it). some people believe it can be learned. some people believe there’s a predisposition for it that can manifest in the first years of a person’s life as long as they’re exposed to a lot of music.
I know one french horn player who was born with perfect pitch, but used extensive ear training to refine it into something closer to absolute pitch: he can tell you exactly by how much a pitch is sharp or flat of conventional tuning (or of absolute tuning, which is a really cool phenomenon that takes up a whole different discussion).
personally, I only figured out that I had perfect pitch once teachers started asking me if I knew that I had it - I didn’t think it was anything special before then. I thought that being able to identify the tonal center of a song or the pitches of everyday objects was something most people could do. so, since I didn’t know what perfect pitch was until well into high school, it’s impossible for me to tell whether the skill was always there, or if I learned it over time.
what I do know is that relative pitch - the ability to identify notes using a reference, i.e. “I know what C sounds like and I can count up or down from there” - can be learned! ear training (learning how to identify everything from notes to intervals to chords to cadences by ear) is an integral part of many musicians’ practice routines. I’d recommend some ear training exercises on musictheory.net, if you’d like a place to start. if you combine those with theory skills (learning to read music), you can read, say, a major third on a piece of paper, and then hear in your brain what a major third sounds like, and then - voilà - sing it!