sing high sounds weird

Hi, I hope everyone is doing good. I am basically trying to sing a song with high notes but I realized that I can sing it but it sounds weird. I can sing well with my chest voice but whenever it comes to my head voice I sound weird. ( I used to overuse my head voice when I was younger but I stopped a long time now is that a reason why I sound weird? ) Thank you.

Also, I am a guy and I am 19 ( people tend to get confused :) )

Hi, Jean! Head voice has a different tone quality than chest voice. While it'll improve over time (as you get more comfortable there and make adjustments), you also want to begin training mixed coordination for powerful high notes that won't be full chest or head registration. 

See below for lessons with explanation and exercises for you:

Article on mix - https://www.30daysinger.com/blog/mixed-voice-why-is-it-so-important-and-how-can-i-develop-it

3 favorite mix exercises (save this video!) - https://www.youtube.com/watch?v=qwiwZ3dS8mg&t=408s

Live lesson on mix - https://www.youtube.com/watch?v=0soCFM4YSIE

How to stop flipping/cracking - https://www.youtube.com/watch?v=6pI9v1YMFN4&t=1s

How to stop yelling/pulling chest - https://www.youtube.com/watch?v=vzObbNv78oA

Thank you so much! 

You're welcome, Jean!