the thing is all the tools really jsut help control the dog. they don't help wtih the training part. You'll get some good tips but I HIGHLY recommend looking for a loose leash training class. We have tons here, hopefully you have some locally as well. they are shorter classes on ONLY how to train your pup to walk (VS a regular class that covers that in just part of one class then moves on).
With pen what I do now is stop when she puts tension on the leash. when she is walking without pulling I praise randomly, and treat randomly. She has issues walking by other dogs so I try to spot them first and get her "working" before she spots them. I let her watch then get her attention and reward when she doesn't lunge. we are taking baby steps there (I am trying to lure less and find the right reward rate to let her "think and decide" but catch her before it"s "too long and she makes the wrong decision".
so once you have the basics, you need to then add distractions like meeting. You'll ideally get some friends help her. you want to "randomly" (but planned!) meet them on the walk but your pup doesn't get to meet them by pulling. she also gets closer as she walks nicely. this may take a logn time the first few sessions.