Doubt regarding angioplasty or bypass.

My father has got CAD from 2016, and in 2016 itself doctor told that there is 90 percent blockage in three main arteries and scared him and immediately got ready for the surgery that day itself, my father was forcefully taken to the operation theatre, but my father refused and came back, he got chelation therapy done once and he's controlling his diet, he has sugar too but he doesn't eat anything at all, he's been taking some Ayurveda medicines and diltiazem and keeping his conditions in control. However now in 2021 he is gets slight breathlessness while walking. So can anyone suggest anything, he also got covid 8 months back and he took treatment for that with remedesivir and other protocol, during covid too he got poor r wave progression in the ecg, recent 2d echo was normal, bp also normal, however now he is fine, attaching ecg. Any advice for bypass or stent surgery ??