Not sure what to do

Hi my father is 96 and has recently had phenomenon along with other related illness ie stroke, pigeon lung, and heart failure. He is currently at home with carers but he is now saying he does not want any care as he can look after himself. He has medication 3 times a day and the cares give him this. He is a very proud person and says he can take his own meds but when I go Round I find meds on the floor which he should have taken… I have left notes for cares to watch him take his meds as his eye sight is very poor… (he has had new glasses but still can not see properly) he has to pay for his care as he Has money so cannot get help… He is old school and very tight on spending it.
He gets attendance allowance and a good pension which will pay for his care and will not touch his savings.

I am very stressed about this situation as I am his daughter and I have taken the roll of the parent now as dad can be very argumentative with me. I also look after my husband who has, had 2 strokes and a heart attack. I just need dad to have care so it takes the pressure of me… But if he refuses and wants to cancel his care what are my options.
I also have an olderly person brother who agrees with me.
We are both finding dad very challenging at times.
Think dimentia has kicked in as he goes to bed them wakes up in the early hours… Between 1 to 3am and thinks it’s morning and has breakfast. When cares go in around 7 they put he is up and dressed and had breakfast… They just give him meds… Dinner time they just give meds as dad had mico meal… Tea call is meds as dad refused meal or has already eaten. Dad does not go to bed he sleeps in recliner chair and he sleeps in his clothes.