Most diabetic meds (jardience, metformin etc...) have a fairly modest effect on blood glucose. So if you take it and continue to live your life in the same manner that you did before your diagnosis, you can probably expect to see an initial improvement, a stabilization, and then a slow decline. The improvement might not be enough to get good control, and you may need meds adjustment.
And yeah, IMO porridge is not a great choice. I'm all-in on a keto lifestyle, and there's no room for porridge in a ketogenic diet. My BG levels are better now than they have been any time in the last 4 years and I'm on fewer meds too.