I get super bad headaches when doing caffeine cold turkey that otc painkillers can't touch (didn't try heavy ones but that's overkill anyways). But yeah cold turkey is the quickest way for sure, it just sucks more.
I'm currently going through caffeine withdrawals lol but it's manageable if you go like 1 cup less every 1-2 days. I heard phenibut can be pretty bad but I have no experience with that.
I feel more energetic if I eat less during the day. I usually don't eat until after 12. If I eat a big lunch or breakfast I get brainfogged for a few hours. Lines up with being a slow I guess.
My dad has been doing yoga literally every day for years, he's nearly 70 and still in really good shape while some of his friends are starting to get mobility issues and stuff.