im looking to get really fit by mainly running/jogging
do any of you know whether i should mainly pay attention to the distance or amount of time i do??

It's not about the amount of distance you cover, it's about getting your heart rate up. So I would focus on the amount of time.

You should maintain a steady heart rate for at least 20 minutes. When I'm on my stationary bike I can keep my heart rate between 130 to 140 bpm for about 30 minutes. Sometimes I can keep it up there for 45 minutes.

When I walk I've gotten my heart rate up to 120 bpm. But I'm able to walk between 60 to 85 minutes.