Guess, you feel you are not worth to perform ibadah (worship) and follow sunnah because you feel you are not good as Muslim?. That feeling is caused by shaytan. That's the satan's way to mislead human.

Just change your way of thinking. Whenever you feel "I am not worth to perform ibadah because I still commit sins", tell yourself "Because I have committed many sins, so I should increase my ibadah. In Shaa Allah, if I close to Allah I can stop commit sins".