Answer:
I am free for the taking. Through all of your life, though given but once at birth. I am less than nothing in weight, but will fell the strongest of you if held.
A hill full, a hole full, yet you cannot catch a bowl full.
I appear in the morning. But am always there. You can never see me. Though I am everywhere. By night I am gone, though I sometimes never was. Nothing can defeat me. But I am easily gone.
I have many feathers to help me fly. I have a body and head, but I'm not alive. It is your strength which determines how far I go. You can hold me in your hand, but I'm never thrown.
This is rectangular, hollow and has a lid, and where you’ll find it you might wonder, it is just six feet under. What is it?
People take me on walks and I run and have fun. What am I?