The lewis structure for ch₃nh₂ whose skeletal structure is ch₃nh₂ is attached.
Carbon (C) is the central atom as it has the most bonds (3) to other atoms.
Bonding Electrons is shown as each single bond between C and H or N requires 2 electrons, and there are 3 single bonds, totaling 6 electrons. Carbon has 4 valence electrons, Hydrogen has 1, and Nitrogen has 5. In total, there are 10 valence electrons.
After forming bonds, nitrogen still has 3 valence electrons left (5 - 2 = 3) and these remaining electrons become a lone pair on the nitrogen atom.
The rormal Charges is evident as atoms have an octet of electrons (except hydrogen, which needs only 2) and no formal charges.