Three things to answer before you start.
1. What's your motivation?
2. What's your goal?
3. Where are you starting from?
i) So you don't get lost ;-)
ii) What I mean is, what's your base-line fitness?
If you've got answers to those, then it'll help give context and a meaning to the next steps, most of which folks here have already mentioned i.e. walk before you run (literally, if you are starting from scratch), get some decent shoes, get some decent routes / loops under your belt, etc.
I started running about 7 years ago, originally as a compliment to cycling. I'd never run before, not even at school (I used to walk around the cross-country course
). I could barely cover 500m without passing out. But 7 years later, I'm doing my third marathon in September (Berlin), have run the Reading half 6 years in a row, and bash out a weekly run between 6-15 miles a week comfortably*. I'm no athlete by any stretch, but my pace isn't too shabby and I've found I'm more fond of longer runs that short. These are things I never thought possible, but all are possible.
Like any cardio work, it'll help with your overall well-being. And your cycling; you'll be able to pedal for longer.
But running is a cruel mistress. Far more cruel than cycling. But that's for another day.
*I say that in severe jest. I'm often creaking for the rest of the day.