Teaching a puppy to come when called isn't very difficult although bear in mind that some puppies do learn faster than others. What I did with mine was wait until they were actually coming towards me then said in a very cheery voice "come". When the puppy gets to you, you should give her a reward such as a small titbit, lots of praise or a short game with a favourite toy. My dogs are motivated by food so this tends to be what we use for training sessions. When they are puppies training sessions should be kept short as the concentrations pan of a puppy isn't that high and you need to stop the exercise before the puppy gets bored. Training should be fun for both you and the dog. In the beginning, never call her when she is distracted as she is unlikely to pay any attention to you so theres no point really
Obviously as you progress, you should be able to call her away from distractions but that will come with time. With training, a lot of people want results NOW but it does take time and its worth doing things properly and not taking any shortcuts as it will give you a very solid base from which to work on.
I would look into enrolling in a training class (that only uses positive training methods) and that will help you learn how to train your pup. Its also very good fun and will be very good socialisation for the puppy. Most puppy books have a section on basic training eg sit, down, stay so might be worthwhile investing in one.