I have red itchy bumps all over my stomach and just started getting them on my arm what ccould it be or how do I get rid of it?

Eczema? Itchy bumps in winter on trunk and extremities is often eczema. Topical cortisone creams--otc or prescription can help. Heavy moisturizing with creams, not lotions will also help and will likely prevent a recurrence. Avoid too much soap and hot, hot baths.