If object made of atoms and atoms are invisible then when we look at an object or touch an object what we see or feel?
One atom is so tiny that it is invisible to the human eye.
So actually each atom is "a tiny bit visible". Let's take 1g of iron. That contains 10^22 atoms.
So 10^22 times " a tiny bit visible" is visible to the human eye.
I hope this simple answer (ignoring the principles behind feeling and seeing atoms on atomic scale) helps you to understand.