Rayna, you need to physically control the puppy to the behaviors your want.
Restrain jumping with the leash. Remind sits with food on the nose. Help the puppy to "sit for a visit". My puppies hear these words every time someone comes up to them. "Sit for a visit". Good puppy, (give treat). Hold the puppy in the sit position as they get petted and treated by the visitor. Release and praise as you move away from the visitor, and ask for another sit.
Your puppy is learning self control, and the self explanatory, "sit for a visit". With my large dogs, it is DOWN when you see a toddler. I also teach this from very early. "DOWN for the baby".
What happens if you don't separate the puppies is they develop a pack bond between them that can be so strong they are difficult to train or take out separately, and don't bond as well with their human pack members.
When you go out with the puppy, always carry delicious treats. Teach your puppy to watch YOU and pay attention to YOU when you are out and about. YOU are the source of all things good, and you are the benevolent but strong leader who will SHOW the puppy what is expected.
So when you are out with your puppy, you will be doing a lot of the "show and tell". SHOW the puppy what you want by helping him to do it, and as he is doing it, tell him the name of this behavior, as you are rewarding him.
You will need to take each puppy seperately to work on these things. When you take them out, take a crate, and leave one in the car, or take one one day and the other the next.