i am not singing to my full potential when I am singing along to the radio why?

Hi, Ethan! When we sing along, we often "under-sing", since we're singing along to another person (the lead singer) and can automatically take the "back seat", so to speak. If you're singing along for pitch matching purposes, great! Once you're confidently singing the melody in tune, you can begin to turn down the volume of the vocal with a tool like this: https://vocalremover.org/. You can also sing along with an instrumental version so the melody is played by an instrument, not sung by a vocalist. Either option should allow you to "take the lead" with the melody still there as a support.