does it become more reactive sodium react with oxidation

No, the reactivity of sodium does not increase when it reacts with oxidation. In fact, oxidation can actually decrease the reactivity of sodium as it forms an oxide layer on its surface, which acts as a barrier to further reactions. However, sodium can become more reactive when it reacts with other elements or compounds that cause it to release its outermost electron more easily, such as in the reactions with water or halogens.