Attention Deficit Hyperactivity Disorder (ADHD) and Attention Deficit Disorder (ADD) are very similar conditions; both show symptoms of inattention and distractability, with the H in ADHD added for additional symptoms of hyperactivity. Someone diagnosed with ADHD will have ADD be default.
Whilst there is no cure for ADHD or ADD, there are different ways the symptoms can be managed to improve attention, cognition and overall wellbeing.