the male is a very submittive fella my girl is very dominent with him and any other dog she meets on her walks the first thing she trys to do is Dominate.Bitches usually do rank higher than the resident dog so that is not an issue in itself at all quite natural, however how do you mean that she trys to dominate other dogs she meets on walks, what exactly does she do? Are we talking that she runs up to play confidently and is not shy or are we talking that she shows some sort of aggressive behaviour towards other dogs male and female? Does she scruff them, how does she act? Also what breed is she as different breeds do interact in differing ways which you may be percieving as dominance when infact it is her way of greeting and moving.
Adult dogs in general are none aggressive towards puppies, though on first introductions you have to be careful as some adults are actually quite fearful of little bouncing puppies, so you need to introduce slowly and give both places to escape one another at times.
I think we need to assess what type of bitch you have first though. As if she is a true alpha then you will need to take the advice of the breeder of this new pup and make sure that she helps you to choose a lesser ranking bitch pup, you don't want the bitch which is likely to be more alpha as you will have dire problems in 7-12 months time when the pup reaches adolescence, if the bitch you have now is very dominant you can't have two with similar characters together, your bitch will either being the elder hold her status if the new bitch is unchallenging or if the pup eventually grows to be then fights will happen.
TBH if you are worried about how your girl will react (it is very difficult on a forum as we can't see her or judge her body language) then you may be best getting another male.