Polarity of Methyl Radical
I think you are getting confused see firstly methyl free radical is a planar with two hydrogens facing each other . The dipole moment vector of the single electron is away from the central carbon
Carbon has Electronegativity value 2.55 while for H it is 2.2 so all the hydrogens have a small positive charge and the carbon has a small negative charge . the direction of the dipole is from negative to positive so the dipole moment vector of the single electron egts cancelled by the resultant of that of the C-H bonds hence it is a non polar structure