Question

what is the difference between cyclohexane and benzene even though both have 6 carbon atom each in their molecule ?

Answer 1

because in the atom cyclohexane every carbon is joined with other in a cyclic order but in the atom benzene carbons are not join with other in cyclic way

Answer 2

Cyclohexane has no double bonds between the carbons, its formula is C6H12, while benzene has 3 double bonds with the formula C6H6. Those double bonds are conjugated with the rest of the molecule, which is what we call an "aromatic" cycle