In my ordinary mindset, I seem to be my body. And obviously I very much depend on it for life and experience. But I don't really know anything about it. There is an infinity of complex processes going on that I have absolutely no idea about. Take breathing - yes, I can control it - but only up to an extent. Try to stop for too long and the body will wrench the control back and do its thing. Try not to sleep, but eventually you will. Aside of control, there is the aspect of awareness. I do "feel" my body to some tiny extent - but all that is indirect, based on where nerves are, what they can transmit, and what of that is made available to my conscious mind. But what is my blood sugar or oxygen level? How many bone cells are in "my" left thumb? I have no idea.
The conclusion/observation is that I cannot really say that I am my body. If I was, wouldn't I have first-hand, complete access to all of this? It seems to be more like a (especially modern) car - I have some control over it, various dials give me some information, and I need it to get from A to B, but I only experience it indirectly, and mostly it does its own thing without caring about me. It is a humbling realization.
Of course, the key question that really matters remains: who/what am I?
There is this strong sense "I am" but I cannot find myself anywhere. The only "thing" I can find is the body, but I've just established that it doesn't really seem to "be me". Being is, but how do "I" fit into it I yet have to find out. Wish me luck :)