Can a Lyrical Tenor/Spinto Tenor expand his falsetto register?

I really need some help with this please I am a mixed Lyrical / Spinto Tenor the reason why I am in between these two.Is because my high school music teacher told me that my range is high enough to go into Lyrical tenor range and low enough to go into Spinto tenor range.I could have got that wrong cause it has been a while since I was in high school.But my teacher never showed me how to use my falsetto register and I really wanted to learn how to use that register.I have bascially had to teach myself I'm 21 I'll be 22 in May.Is it to late to expand my falsetto register can anyone give me any tips or songs to do or listen to too make my falsetto register higher?Thank you for taking the time to read and answer my question.