Hi i have a question on my hands i started getting a itch a tiny pimples when rash it it's itchy am i allergic to sun or type of soap? "

Photosensitivity?: Your description sounds consistent with an allergic rash. If so, likely from soap or perhaps a skin lotion; sunblocks are common causes. True sun allergy is very rare, but other allergens can work together with sunlight: some cause "photosensitivity", with rash mostly in sun exposed areas. Avoid the soap or other lotions, etc and see your doctor or a dermatologist if the problem still continues.

Rash: You really should see your doctor and/or take pictures of the rash so that even when it isn't there you can show the doctor. It could be hives but it could also be contact dermatitis and/or photosensitive light eruption. If it is only happening on your hands but the rest of you is exposed to the sun, then likely it is something different.

See a derrmatologist: Allergies which are turned on by sun exposure are a large field. But your problem is most often a skin disease and not allergy. Caustic soaps are often irritating. A skin DR will help you.