1. In the environment oxygen is often found with hydrogen. It is water molecule (H2O),so it is closely related to hydrogen (H). Water (H2O) is an oxide of hydrogen and the most familiar oxygen compound. Hydrogen atoms are covalently bonded to oxygen in a water molecule [Wikipedia].
2. If you have a task to show what element has similar chemical properties to oxygen. Similar chemical properties to oxygen have Sulfur (S), Selenium (Se), Tellurium (Te), Polonium (Po). All these chemical elements are analogs of oxygen. Their chemical properties are determined by the number of electrons on their external layers.