Possible to animate avatar in Unity?

Hi,

I have a question (maybe basic) which is:
Can I animate an avatar in Unity?
I have a Humanoid model and an Avatar/skeleton with that. I want to be able to animate the legs so they rotate with pedals of a bike.
I prefer to stay away from other tools such as Blender and making animations in that, I want to try do the animating in Unity.

Is this possible? if so how or where do I start?

Thanks,
Kim

Yes, use the Unity Animator