Fe+CuSO4->FeSO4+Cu.... what is being reduced and what is being oxidised?

nothing is oxidised or reduced. but as iron is more reactive than copper, it displaces copper from it's salt solution.
oxidation means addition of oxygen or reduction of hydrogen.
but in this equation hydrogen or oxygen are not involved.

as iron is more reactive than copper, it displaces copper from it's salt solution.
there is substance oxidised or reduced because the above reaction is a displacement reaction.(reason is given in the above line)
redox reaction is a process were both oxidation and reduction takes place simultaneously.
and oxidation means addition or reduction of O or H respectively with any element.
reduction means addition or reduction of H or O respectively with any element.

nothing is being oxidised or reduced. this is an eg of single displacement reaction wherein a more reactive metal displaces the lesser reactive metal from its salt solution. we know that iron (Fe) is placed above copper(Cu) in the reactivity series therefore iron is more reactive than copper and hence it displaces copper from cuso4 solution.
in oxidation reaction either oxygen is added or hydrogen  is removed. eg rusting of iron
in reduction reaction hydrogen is added or oxygen is removed. eg hydrogenation of oil

Nothing is being oxidized.

NOTHING IS GETTING OXIDISED. IT IS AN EXAMPLE OF DISPLACEMENT REACTION.