I'm the only 1 in my immed & extend family w/ hypothyroid, psoriasis, Fibromyalgia, auto-immune, rosacea, & overweight etc. Why & are they related?

Some are. Hypothyroidism and possibly psoriasis (the jury is still out) may be considered autoimmune but not rosacea or overweight condition. Being overweight increases your body core temperature and thus worsen rosacea. As for fibromyalgia, we are still in the dark on the mechanism. Belly fat also makes one more prone to inflammation.
Possibly. Obesity, especially severe obesity, causes inflammation which can sometimes cause symptoms of diseases like fibromyalgia. Additionally, new studies show that obesity may actually cause a relative hypothyroid state (as opposed to the traditional idea of hypothyroidism causing weight gain). There is also some overlap of inflammatory and autoimmune causes for diseases, and much still to learn.