Training a Foster

I am training a pit bull mix named Bella. She is very reactive to toys and play time. She came from a broken home and lord only knows what else happened to her so she is very protective of herself with other dogs. Our first session was on 1/4/23, and i wanted to see what she could and couldn't do. She not very well trained on leash walking so I am going to work with her on that, as she is very high strung and uptight. I practiced come, sit, down, stay/wait with her and she did very well to say the least. Her attention span is of a toddler lol so I need to be where there are little to no distractions so I can have all of her focus and attention on me. She is a very loving sweet dog when she is by herself with someone but she tends to not really know how to play right with other dogs. I don't know much of her past but I can see she wasn't very well socialized as a puppy. She is always tense and always on the defensive side with more than one dog around, so I have to keep her secluded for now until I know more about what to do with her. She is looking for a single family home and I know my home is not the right place for her to be as I have very active children---which she is very good with, except little kids under the age of 7yrs old. She won't bite but she will get overwhelmed because as a mother of a 3yr old daughter i have to really watch her cause she doesn't know how to approach dogs yet so she gets overly excited. some dogs don't like that. With that being said, I'm looking forward to working with Bella more and more as the weather hopefully improves. She is very smart to say the least.