Is there a c25k type thing for cycling?

[Titsalinabumsquash]

I am trying my level best to improve my fitness and lose some weight.
I've lost over 30lbs since dd was born 4 months ago, but I'm really unfit!

For various reasons I can't get out and exercise or attend a class or gym but I do have an exercise bike in the house that I can use early mornings and at night time. I like the idea of a slow build yo,and guidance like c25k, is there something like that for cycling?

I'm trying to make the best of what I have and some advice would be great.