I am not sure the question is correctly formulated. I am guessing that you mean whether the nanoribbon has a zero energy bandgap and there exists a point in the 1D Brilloiun zone where the conduction and valence bands touch each other, meaning that the nanoribbon is semimetal, similarly to the pristine graphene. In any case, you have to calculate the band structure along the nanoribbon axis to answer these questions.
