"Best way of starting to build up a team?"

#PokemonGO: Hello, im currently close to lvl 30 and got almost no good pokemons and i want to start taking gyms and raids soon.Im wondering whats the best way to get the meta pokemons? I searched a bit and people suggested to try to get evees and then taking on Machamps which seems to be one of the most lasting meta pokemons. Is this advice still valid or what it the best path otherwise? Also is there any trick to get myself eevees? I just have seen one eevee once via /r/TheSilphRoad https://ift.tt/2EPIXeA