hi i always take my 16 week old pup out for walks but she barks at everyone if people talk to her shes great what can i do she also backs away so i think she is nervous what can i do shes ok in house when anybody visits. any advice would be great

For a start don't try and comfort her when she is nervous...you are only reinforcing unwanted behaviour. Your best bet is to take a nice treat out with you and when she barks ask her to sit and 'look at me'' ....when you get her attention reward her.
Take her to a good socialisation puppy class and get her out and about as much as possible.
Archer