Salutations!
If you were to study bodies of water,landforms, and the natural resources found on our planet, you would be learning about -----------
If you were to study bodies of water,landforms, and the natural resources found on our planet, you would be learning about physical geography. Physical geography deals with modifying Earth's natural features, basically anything related to natural features. Some of the examples are: tides, waves, mountains, climate etc.
Hope I helped :D