Vegetables - all are good except avoid nightshades (white potatos, tomatos, onions, peppers) - best are leafy greens, broccoli, sweet potatos
Fruits - all good except avoid oranges, grapefruit, tangerines - bananas are bad, I'll explain later - some people have trouble with melons because they tend to mold faster than other fruits
best are pears and berries and cherries
Meats - scales and feathers instead of fur and hooves, in general
Grains - millet, rice, quinoa the best - wheat, barley, oats, corn the worst
Given the 4 foot long colon in a human, we do best wtih foods that have a transit time of about 2 days. The above foods fit that criteria. A few bad examples:
Pork - 7 to 9 day transit time
Banana - 7 day transit time (putrifies in gut)
red meat - 5 day transit time
flour - sticks in gut and to colon walls
By the way, yogurt is really the only cow product that is good for you (it is fermented, so chemically changed from milk). But don't get the flavored fruit on the bottom stuff - get an organic plain yogurt and add your own flavoring - highly beneficial.
I've taken a lot of supplements over the years. I think most things off a shelf are garbage. There are exceptions, like Emergen-C in the packets are terrific. The stuff in the health food stores is equally bad quality, in my opinion, just with a much higher price tag. I recently found Nutrafina and have switched over almost completely to their products. Before I would take vitamins "on faith" because I really couldn't identify any real change when I was taking them. I can say now that if you can't tell a difference, you should be taking something else, because now I can tell even if I miss a day of my supplements.
Sounds like you're on the right track, asking questions and gathering info! Good luck!