What should I do about my health problem from 24 June 2024?

I am 77 years old. I was taking medicine for high BP from the age of 50 years.I was very active doing yoga regularly in the morning and doing walk in the evening. I do not smoke and do not drink as well. I am a person with height weight normal as per the standard chart. I was very active doing my job and never use to get tired. I worked for six years in Central Govt, thirty years in PSU and seventeen years in Private Organisations. I used to believe that " a Person should never retire from work". I stopped going to work from March 2020 after the Covid 19 spread in India. During a routine check up, my doctor mentioned on my prescription as "Stable Angina". I asked about it but he replied, it is nothing, do not worry. I was not having any pain etc. But this remark of Stable Angina. was written on my prescription on every visit. In June 2022, I got a CT Angiography done just to know the deposits in my arteries. It was found to be more in all the five arteries. But I had no symptoms of any pain or breathlessness while moving or working.In August 2022, I got some problem in my left eye, went to eye specialist, he observed a little deposit in eye nerve. He tried to break it but could not. I went for Angiography. All the arteries were found with deposits but still I had no pain etc. I was operated for Heart By pass Surgery on 22.9.22 and released from Hospital on 1.10.22. I was put on High Protein Diet. During Jan 23 to July 23, my Blood Urea Nitrogen & Urea got up the required level.High Protein Diet was stopped and advised take more Fruits. BUN & Urea came normal. More fruits were being taken. It caused potassium level to go up. Then in fruits also restriction imposed on banana, coconut water & citrus fruits. Now I am on restricted diet. BUN & Urea are normal but potassium remains fluctuating. Now I am alright but feel very weak. I do little walk but get tired soon. I am not able to do yoga due to low energy. Vitamin supplements are being taken but not getting strength. Even feels stability problem. While standing feels giddiness and feels that i may fall. I am also feeling severe pain in my arms muscles. Now I am taking medicines for BP, Cholesterol, Blood Thinner, Enlarged Prostrate Gland, Vitamin supplement. I always think why I am feeling so many problems after Heart Bye Pass Surgery. Please advise.