Q&A for How to Evolve Shelgon

You can teach most Pokemon TMs and HMs or by leveling them up and evolving.

No. Shelgon only evolves via leveling up. Typically, evolution stones are used for certain species of Normal, Fire, Grass, Electric, and Water types.

It would depend on which generation you are playing, and in some cases, which version. You should check resources like Serebii or Bulbapedia for more information on exact locations for a specific game.

Depending on where you are, one thing is that Pokemon of the 3 basic types, (fire, water, grass) and electric are all not very effective against dragon types, use that to your advantage.