Undigested food can be caused by a few factors. One is how much you are chewing your food (if its not chewing 30+ times per each bite then this is it right here).
The second issue is that you likely are deficient in enzymes and/or HCL. If you take some bitters or an enzyme product, this will help you break down your foods better. Chewing also produces enzymes but your body may not be producing all of the ones you need.
What is the breathing symptom you are talking about, please explain this further. This could be due to the toxins flooding your lungs.
The skin problems and lung problems are both related to toxins flooding these organs.
Is the rooibos tea caffeinated?
I do think you need to eat more; you need to be full like its thanksgiving after each meal. You’ll likely feel a lot better. Additionally, you likely will feel a lot better if you were to eat meat because otherwise you’ll develop mineral deficiencies and other nutritional deficiencies. Minerals are found within the meat and are quite important. My naturopath recommends plenty of protein on the diet and gets screamed at when he tells his patients to eat meat who are vegetarian. When they finally give up and try it months or years later, they come back and tell him he is right.