What level are you?? Walk w/ Pupitar!(Very nice Pupitar btw) The important thing is don't power anything up yet!! :) My key to the lower levels is to obtain as much Eevee, Pidgey, Weedle, Hoot-hoot, Zubat, and whatever common spawn candies as possible and use most of them as Xp gainers you want to level up asap and evolve high cp/lvl eevees along the way! :) awesome stuff seeing new trainers.
+Editing because I forgot to add farm Magikarp (If you live near water it's 100 catches provide you transfer every Magikarp you catch or around 50 if you use Pineap berries) Gyarados will prob be your best attacker. All of his/her move sets are pretty solid for general attacking.