My son became a vegetarian around 6 years ago, he eats nothing with eyes, but still eats eggs and dairy products,he has had no bad effects, he lost weight without even trying. His reasons for going vegetarian was because of a video that he was sent that showed some bad stuff at a big farm, and also from a big kill place, he was a very big meat eater before,
He eats a lot of beans, rice, tofu (nasty stuff), veggies, fruit, whole grains, if he is having a busy day he will make himself a protein shake, using a plant based protein powder, he eats cheese, drinks milk, eats ice cream,yogurt,he eats no more than 4 eggs in a week. He has tried a lot of the fake meat stuff you can buy, some has been good, some not, his favorite is a vegetarian ground beef stuff, it looks like cooked ground beef,add it to anything that you would normally use ground beef, comes in the frozen section,some of the frozen meatless burgers he has found that are okay, he has found the chicken stuff to not be very good, except for some fake wings I found for him one time, he has tried the fake bacon and lunch meat stuff, he didn't like them. Walmart here in Canada carries a lot of different vegetarian frozen foods. I have found with him it's all trial and error.
The hardest thing that I have found is going out to eat at a restaurant, he usually only will order a veggie omelet, or a build your own pizza. He is very anal about getting any animal protein, as he says it will make him very sick, because he hasn't ate meat for so long, he gets concerned with cross contamination,