I’m going insane day by day. Waswas has ruined my life, I can’t control my anger, and I have no willpower to keep living like this. I’d never leave Islam, I’d rather live and die crazy. I keep repeating the shahada and making ghusl daily due to fear of having committed kufr. I dont know what to do.

Look grap a paper and pen, write down the answer to all your questions is yes you are a Muslim no you are not a kafir. Never ever ever take the shahadah again and ghusl is not mandatory to do anyway. Listen to what I am saying you sre a Muslim you are not a kafir never never take the shahadah again! Also seek medical help to calm u down and help solve the problem.