A lot of people tend to ask us vegans where we get our protein. It’s actually not hard to get protein on a plant-based diet at all. Have you ever known someone who is protein deficient? If you search Google Images for “protein deficiency” the first thing that comes up is starving children in third world countries. The only way to not get enough protein is if you are simply not getting enough food at all. It would be starvation. Regular fruits and vegetables contain about 5% protein per serving, just like a mother’s breast milk contains. That 5% is enough to make a human baby grow very rapidly in just a few months. Our diet should only be about 10% total protein as a whole, and that's the maximum. Just eat enough, and you will get enough. :) I would highly suggest watching videos by Dr. John Mcdougall on Youtube. He’s awesome!!! :)
Check out what Dr. Mcdougall says about protein! :)
Other people might ask "where do you get your calcium if you don't consume dairy?" The answer to that is simple. If you're getting enough vegetables (especially leafy greens), you're getting enough calcium. Also, most non-dairy milks (made of things like almonds, soy, rice, oats, hemp, cashews, hazelnuts, etc.) tend to have 50% more calcium than animal milk.
Finally, people are often concerned that if they go vegan, they won't get adequate vitamin B12. This can be a possibility as not many plant foods contain it, due to modern farming methods. B12 comes from bacteria in soil, so when vegetables are highly washed and aren't grown as naturally these days, B12 is much more scarce in produce. First of all, ALWAYS WASH YOUR PRODUCE. Dirty produce is NOT a safe or sustainable way to get your vitamin B12. However, there do happen to be some plant foods that have it. Foods like mushrooms, edible seaweed (like kelp), spirulina (a kind of algea), nutritional yeast, many soy products, fortified non-dairy milks, and fortified breakfast cereals are all sources of vitamin B12. The most reliable option, though, is to take a sublingual B12 supplement. Make sure, also, that is is not from animal sources. It should say so on the label. Taking it once every 1-2 weeks is perfectly acceptable and gives you just the energy boost you need. :)
Vitamin D is actually the easiest vitamin to put in your body, as long as you're able to get out in the sun every now and then (and don't over-do it either. ;). Vitamin D can also be found in good old orange juice, and most non-dairy milks.