Right now I'm 16 years old and the lowest note I can reach is a very forced B1 (not vocal fry). I have been able to reach down to an A1, but I can almost never reach lower than A#1 at the moment. What can I do to extend my voice to a G1 (not vocal fry), just around 2 notes/5 seminotes lower? Wait to get older? Or are there techniques to master?
I would personally recommend Brett Manning's Singing Success program. It helped me increase my range a full octave. I think you would find the same success if you stick with it and practice daily.
The only downside is that is pricey and you have to be willing to pay. Although if you can't afford it, Brett Manning studios and Singing Success has some great tips and singing techniques on their youtube channel for free. Good luck and keep singing!