What are some ways in which environmental resources are important to human health?
The "environment" affects the life of every species within it.
There are no "good" or "bad" environments - just environments that are more conducive to certain life-forms. Most life forms on earth are in the water!
So, you need to be specific about the environment conducive to human life. In all cases, the environmental resources required for any life form are primarily food (and water). Without a food supply (including the entire chain leading to a particular form) the rest of the physical resources will be useless.
After food, a means of protection from the weather elements is the next priority. That means natural caves, coves, windbreaks, and materials to construct shelters such as vegetative cover.
Next comes external energy (non-muscle) for improving living conditions through food modification (cooking) and temperature control in the shelter.
All of these are necessary environmental resources to sustain human health and existence.