I personally don't think the neighborhood walk is necessary (and I wouldn't risk it). Are you picking her up at the breeders'? If so, I would ask them if Bentley can get out there and do a meet n'greet. If you want to intro them on another neutral property, perhaps you can take them to some friends' or your parents' yard (with no parvo history) and let them meet. Otherwise, between the meet at the breeders', smelling/seeing each other during the car ride, and a meeting in your front yard, you should be good. I wouldn't feel comfortable taking a pup that young on a neighborhood walk or anywhere that is commonly used public grounds.
After the initial intro, I'd still recommend keeping them separated (but within sight, if all is going well) unless you are actively supervising. It might help during the latter times, too, if you have on or both drag a leash for any quick removals. Lots of treats and use of a positive interrupter, and no tense leashes.
Pups can be brats to their new older companions, plus it's quite an adjustment for some dogs, so pay close attention to Bentley for signs of stress. Make sure he is getting extra attention/play/treats on his own, but also try to incorporate the new pup into some those fun times, too.
Some people recommend letting both dogs settle in, knowing there is another dog in the house for a few days, before actually letting them spend time together, but frankly, I'm too impatient for that. I just do closely supervised interactions and separate them when breaks are needed.