Can ethanol be both a Lewis base and a Lewis acid?
Lewis acidity and basicity require some amount of context because they can't function in those roles without at least a putative base or acid, respectively. Certainly the oxygen here has a lone pair so it could be basic, and the $\sigma^{*}$ orbital of the O-H bond (on the hydrogen side) can accept an electron pair. What matters more is the context of what acids and bases are present to interact with these moieties. There is no reason why these pieces can't separately fulfill their roles independent of each other.