Ok, a few benefits after I lost sixty pounds

That asthma inhaler has been idle

My diabetes has gotten orders of magnitude better

So has my blood pressure.

Start by literally removing franken foods from your life. The added sugar in industrial foods is not a minor thing. The sugar is the whole point.

Add single ingredients to your life, yes that means salads, that means brocoli.

Remove seed oils from your life, and if you eat processed hyper palatable foods, that is easier said than done.

Don't drink your calories, this one is damn easy.

But if you remove that sugar, it's inflammatory. Should help your breathing issues since some of that is inflammation.

I personally follow a low carb protocol with daily intermittent fasting, because T2D and it has helped immensely. As to BMI, you are correct. However, do a waist to height ratio. It is even less forgiving but far more predictive. this is why Japan has adopted it.

Caveat, BMI is great at a population level though.

As to your dog. We have a chihuahua mix, who has back issues,. We keep a tight eye on his weight, because weight will only make it worse. Yes, the pooch has a profile on our scale.