Fasting will help the inflammation, as well as losing weight. They say every pound lost equals 4 pounds of less pressure on your knees, so keep that in mind while you go.
Honestly I break down when I try to keto. I see this as a lifestyle. I would do first month just focusing on the time window and trying to generally eat better. Then second month start changing foods. If you feel better on keto go for it, but if you hate life on it then I would not do keto
OMAD is fine, especially if you’re lowering your total caloric intake. I did OMAD for a long time. Was good. Key is consistency. Just don’t drop. You’re not gonna see results every day, you’re gonna have ups and downs, but the proof is there and 100% works. Just stay on track 👍