How can I help my son?

Can anyone please tell me there is still hope in helping our 7 year old boy??? He has a hard time with his ADHD, with it comes a lot of behavioral issues, whining, talking back, just plain being so so rude and mean lately to his dad and I, sister and others around. He’s been put on a medicine for ADHD but isn’t on it anymore but my main concern too is the attitude and behavior. I’m struggling so bad, He’s clenches his fist and screams when he’s upset and mad, always crying. It’s so hard to see him so upset and he knows how much he is loved. Not sure if there is anything to help with his mood, and adhd? Somethings got to help! I see him happy but more so upset and rude lately. PLEASE mamas any suggestions as where to get him help? We are close to grand island and york, but wouldn’t mind driving a bit.