Welcome!
I don't know about the Bowflex--I've never seen one--but I can't imagine why you couldn't do hubby's workouts. What works for men works for women also. You're very unlikely to turn into Arnold Schwarzenegger by accident.
As far as cardio goes, it really depends on your current state of fitness. You're not very overweight but you also say that you've never exercised, so it depends. For some people, 15 minutes of walking counts as a lot of exercise; others can run for an hour without much trouble. I'd say, ideally, that 60 mins of cardio 5 times a week is best for weight loss. But if that's too much to start with, do 45 or 30 or 15 and work your way up to the longer sessions. If you don't run, walk or walk on an incline. Just don't push yourself too hard too soon. You don't want to hurt yourself.
Have fun!