What should I do? Please help I’m desperate.

Here's what i think: You aren't getting any relaxing time to yourself without your dad. You aren't able to reflect for yourself. Do your hobbies/passions. Or possibly be your own person.
If he is able to afford the services he needs, you should use them. Maybe he doesn't want to be left with complete strangers, or embarressed for somebody else to do certain tasks , such as taking him to the bathroom. In which case, be with him while the other caregiver is there to see if he/she would be a good fit for your dad.
Everyone needs time away from their parents, its just human nature. You need time for yourself to just live, breathe, feel like an independent individual instead of a sidenote/sidekick. Allow another caregiver to take care of him for a couple hours so you can figure out what you want to do with your life. Being expected to take care of him always is very giving & self sacrificing on your part but if he can't appreciate your help and all that you do(which is probably a lot) then you need to do something that'll make you feel appreciated and worthwhile. You need to tell him how much your burned out and what you need; not his needs , not about him. If he can't compromise(or at least give you an ear) then you need to leave him & start living your life. keep coming around to prove that you do care.

Your profile says he is living with you? Or r you living with him. Makes a difference in how you handle the situation.

If you r living with him, save your money and get a place of ur own. Do not quit your job. Dr. has told Dad he needs more care, you don't need to be the one to do it.

If he is living with you, the next time he is hospitalized tell them you can't care for him. The doctor says he should be in a home, that will be a good time to have him evaluated for one.

Are u in the US? I ask because I can't believe that when u left school someone didn't question why. A 15 yr old should never had to care for someone.

I think that I would question what is wrong with your dad that he treats you and others so horribly. Does he have some mental condition that causes it? Does he have a personality disorder? But, whatever it is, it's not acceptable. I think you know that, but, for some reason accept it. Apparently, others in the family do not accept it. I think that I might consult with a counselor who could help you sort through your feelings and help you build tools to make some decisions about your situation. You may want the unfair treatment to stop, but, not know how to make it stop. You may realize you want boundaries, but, struggle to make them clear. You may be miserable, but, not have the skills to remedy it. That's why I think a counselor could help you. It's not a quick fix, but, a process, imo.

To me, getting out of a toxic situation is vital, imo. You may not be able to change him, but, you can be your own advocate. His demands and criticisms don't sound very reasonable. Perhaps, allowing him to make his own arrangements would be something he could consider.

There is simply no teen who should ever be placed in the position of caregiving for a parent, most especially one that is verbally abusive and unappreciative of that care. It’s past time for you to get out of this situation and make a life for yourself. You’ve been used long enough. Please let us know more about what kind of support you may have available or need so advice can be given. And decide that your dad can and will be fine without you, he’s got the means for help other than you

Hi Isamar
Are you the only caretaker for your father? Do you have siblings? Where is your mom? Your fathers siblings, his parents. Is it in your culture for the daughter to care take her parents at such a young age?
You list an extensive number of health challenges for him. To whom does he address his remarks about you? Do you have health professionals coming to your home?
Does your dad drive? Does he see physicians? Are you involved with this medical visits, giving him his meds, speaking with his doctors?
Give us more information on your situation so that we can give you a better idea of how to go forward.
I know it will be hard, but as you are an adult now, it's time to make a life for yourself. Do you have anyone in your family or friends who might be willing to support you in a decision to leave and begin your life?