Ask HN: How did you start exercising after being completely out of shape?

I'm a software developer in my late twenties and I'm overweight, anxious and am currently doing nothing about it. It's been like that for last 4 years, and I need to do something about it.

I was wondering if you could give me some advice or your stories how you've started exercising given that you've been in similar situation as I am currently.

I've googled some of the programs but it all seems so tough for person like me. I don't know with how much intensity I should start and what to do to achieve maximum results - both on being less anxious and getting into shape.