There is no "thing". Thing-ness is a concept created in our minds by the way our minds respond to physical stimuli.
And the "thing" in your mind is not the same "thing" that produced the stimuli.
All "actual" physical stimuli (that we can perceive) becomes immediately conceptualized in our brain. It's compared and contrasted many, many times with many other recalled experiences of physical stimuli until this experience is contextualized, and labeled, and adequately (we feel) conceived. And that conceptualization gets added to a bigger, more inclusive set of them. And those to yet another, even greater set, and so on until everything is being fit into a very large elaborate conceptual complex that we call "reality".
It gets incorporated into our mental model of reality: our understanding of how the world works, which us different from the world itself.
And we really want to believe that our conceptualized "reality" is an accurate representation because if it's not, we are living life blind and rudderless. And that's very dangerous.
Right: we want our mental models to be as accurate as possible. But they're still models.
But the drawing is of the concept of a "bicycle". And the metal thing with the wheels is a functional manifestation of the concept of the bicycle. Neither of these is more or less "real" than the other.
My understanding of a bicycle includes that it's a thing that a person can sit on and pedal to make it move, and that can steer and stop. Whatever concept is in my head, if it can't do these things, I can recognize that it isn't a bicycle.
But it's not those things that define a bicycle.
Right: the attributes of a bicycle define a bicycle. Those attributes are missing to some degree from any human conception of a bicycle.