My Hibiscus Plants Have A Fungus Type That Is White In Color, How Do I Get Rid Of The Black Bugs?

My guess is that there might not be enough nutrients in the soil where your Hibiscus is planted.
 You could try using an all purpose fertilizer around the outer perimeter of bush's width. Then water it in good. Give it a couple of weeks and it should perk up.
Hibiscus, as a rule, do not like a lot of water, so just water it enough to get the fertilizer in the ground. Otherwise, the leaves will probably turn yellow from too much water.

Hibiscus plant, also referred to as the Rosemallow is a flowering plant normally found in the tropical and subtropical regions throughout the world. There are many types of fungus's that effect the Hibiscus plant and the treatment is different for each one. See the link below for details on types of fungas and their cure.
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