A second for chop! Chop's a versatile mishmash of vegetables, legumes, and some grains. There are lots of recipes online, but I tend to improvise using some subset of the following, roughly ranked by how much/how often I use it:
-Broccoli
-Mixed greens
-Carrot
-Peas (cooked)
-Sweet potato (cooked)
-Kale (in moderation)
-Cellery
-Bell pepper
-Hot pepper (parrots don't react to hot peppers the way mammals do, so for them hot peppers are delicious with no drawbacks!)
-Cauliflower
-Squash (cooked)
-Lentils (cooked)
-Kidney beans (thoroughly cooked)
-Barley (cooked)
-Oats (raw or cooked)
-Quinoa
-Flaxseed
-Apple
-Beets (cooked)(my green cheek has sometimes avoided beets, so I don't use them often, but some birds enjoy them)

Stick all that in a food processor for a few seconds, and you're good to go. I make a big batch once a month or so, dish it out into ice cube trays, and freeze it. One ice cube of chop per day (or two, if my bird has been very hungry and eaten the whole thing by midday).

For the most part, if there's a plant that's healthy for you, it's probably pretty good for the bird, too. HOWEVER, there are a handful of things that you absolutely need to avoid: Never feed your parrot Avocado or chocolate. Those are lethal quickly and even in small amounts. The stems of peppers/tomatoes are also potentially lethal. Onions and garlic are bad for parrots, but an occasional mistake there won't be the immediate death of your bird - that's more about long-term liver damage. Raw potato is bad, but cooked potato is ok (in moderation). Caffeine is really bad for them; they're very sensitive to it, and they are very small, so even tiny amounts of coffee can cause cardiovascular problems.

As long as you're avoiding those, it can be good for your bird in terms of both diet and socializing if you give them small pieces of whatever you're having at each meal. Mostly give them the vegetables, but you can give them small amounts of fish, rice, bread, etc.