Substituting Running with Biking...?

I'm a 15-year-old high schooler who is active in every running sport (cross country, indoor track, and spring track). I've been running an average of 40-minute 6 miles a day every week since the end of school, which was about a month ago. During this time, I started noticing a pain in my hip. My mom told me to not run for two to three days, but instead, bike. Because I am new to working out on a bicycle, I was wondering around how many miles I should bike in order to reap the same benefits I would with running 6 miles a day. Thanks.