So sorry to learn your Dad is unwell.
My lovely dad had cancer spread to his bones, which affected his mobility, he also had atrial fibrillation and other issues. In terms of support I arranged a cleaner for his home, did his food shopping and made him meals for his freezer too. He lost his appetite so we encouraged little and often. He was very keen to stay in his own home so I arranged a social care needs assessment which lead to various aids such as raised toilet seat a fall alarm a walking trolley aid etc.
sadly we both had to accept his need for nursing care eventually and palliative care, dad was resistant to pain relief initially fearful of sedation but the nurses managed to control pain and enable him to chat etc in between his many naps until very near the end.
We even took a little fridge into his room so he could enjoy a glass of wine or a gin with his visitors.I was fortunate I was able to take a break from work and spent as much time as I could with Dad during the last months of his life. Dad had anxiety so that was managed along with physical pain.
I can only suggest you spend as much time as you can with him, be guided by him what he wants and needs, and accept all the help you can get for him ( not that it’s easy gettimg help) look after yourself too x