It sounds like an energy problem! which is understandable with a pitbull cross. They are great dogs just a lot of energy. I have found in my city that some of the local daycares offer treadmill training. If you have a treadmill you should consider putting her on it for a little while everyday. She may start to really enjoy that! Otherwise doggy daycare is always an option.
You could take her to the dog park and train her with fetch, so you can play when you go on off leash walks. Pitbull crosses are a high energy breed so those are just some suggestions for the energy. Draining their energy is going to make any training or behaviour correction a lot easier.
What might also work is really treating her like she has a job. Everything she does can be an opportunity for her to do some tricks or some sort of command. Keep really small treats around or even use her dog food to be used for motivation to perform commands. (depends on how food driven she is for using her regular dog food). I would also establish always having to perform a command around certain activities. Like going on leash, always make her sit first. Then when she sits you can put the leash on and reward with a treat or praise.
Pitbulls are intelligent and they want to please so the more jobs you give them and training the better they will do with your expectations. As for jumping out of the window, teach her the stay command and make sure you can always reward her at first when she does stay. You can find lots of tutorials on the internet. You need to focus on really only rewarding her when she is being more calm than normal/or in a calm state.
If you have a family and the space in a yard you can place games like having people stand on opposite ends of the yard and calling her, and rewarding with a treat when she comes. That will get her running back and forth between everyone and will drain energy to.
