Ok , first u do ur father full check up , like CBC ,
HbA1C ,
Lipid profile, KFT,
LFT, ESR , chest xRays , CT Brain, USG abdomen . Ur father having cramps in hand and legs so i think it’s vata problem. And for vata problem In Ayurveda there is Panchkarma treatment is best for that , it’s very usful in old age and no side effects, Panchakarma is a full body servicing .