Quick take
Identify whether the odor is in hot water only or both hot and cold, then test the well. Whole-house oxidation/filtration is a common treatment path when hydrogen sulfide is confirmed in the source water.
Best whole-house category: oxidation + filtration
Air oxidation and regenerating media are common choices when sulfur odor originates in the well. RKIN and SpringWell offer systems aimed at sulfur, iron and manganese combinations.
Hot-water-only odor may be a water-heater problem
If cold water smells normal but hot water smells like sulfur, inspect the water heater before buying a whole-house filter.
Carbon can polish odor but may not solve the source
Carbon can improve taste and odor, but persistent hydrogen sulfide at meaningful concentration often needs oxidation or another upstream treatment step.
Test first
Well chemistry, pH, iron and manganese influence the correct treatment train.