Is your home listed for sale, or are you looking at public records info? If it's for sale, you should contact your REALTOR and have it corrected in the MLS. They can also edit their own listing info.
But if you're referring to your home's public records info, you'll have to take that up with the county assessor's office. But you could be opening a can of worms. If you're trying to update things like square footage or bedrooms and bathrooms.....first ask yourself -- WHY? If you're adding SF or BR/BA then you better be sure that the work was permitted. AND...if it was...you're going to get the lovely benefit of paying HIGHER TAXES. So again..I'd figure out what you're trying to do and why is it important. Good luck!