I know some vegans/vegetarians, so I know the answer to that "B12" question.
Vegans get their B12 (and other B vitamins) from "Nutritional Yeast".
Vegetarians get B12 from "Nutritional Yeast" too, and they also get it from eggs, and various dairy products (milk, cheese, etc.). They all get omega-3's from nuts (walnuts), seeds (chia, hemp, flax), and certain vegetables (Brussels Sprouts, for example).
The money-bags of the loony left (Soros, WEF, Bill Gates, etc.) are soon going to try to make carnivores, omnivores, vegetarians, vegans, (and anyone not in that billionaires club) eat bugs, so it might be better for all those groups to stick together in fighting those rich evil nutbags.