Most meat is what’s called a complete protein; that is, it has all 20 amino acids. Most non-meat sources aren’t, but that doesn’t mean that you can’t get all of them. You just have to eat more than one protein source.
Complete proteins have all 20 amino acids, fortunately, the body can produce all but 9 amino acids (called essential amino acids) which are needed in roughly equal amounts. Certain foods have incomplete proteins which can eaten at, or near the same time, to have the benefits of a complete protein. This can be fairly easily allowed for in storage preps but about when they run out and what you eat comes out of your garden?
A classic combination like rice and beans would be great. Most beans are low in methionine and high in lysine, while rice is low in lysine and high in methionine but together you have a protein content on par with that of meat. But few of us can grow rice, however, the protein in wheat is pretty similar to that of rice, in that it’s only deficient in lysine. Chickpeas have plenty of lysine, giving us all the classic Middle Eastern staple hummus and pita bread. Legumes like beans, lentils, and peanuts combined with grains like corn (an American Indian staple), wheat, or rice for a complete protein. Except for rice and peanuts, I can grow these here in the North.
While beans are normally low in the amino acid methionine, soy bean is a complete protein and a go-to substitute for the meat in the orient. I can grow them too.
Ezekiel Bread, a combination of wheat, barley, beans, lentils, millet, and spelt is a source of complete protein rated 84.3% as efficient and comparable to that of milk or eggs. Lentils are similar to the amino acid profile of other legumes such as kidney beans or black beans which can be substituted for them.
The total protein content of spelt varies (a relative of wheat) is around 14.3% while soft wheat is 10.5% and spring wheat is 9.1% but similar to durum wheat at 13.8%. The sequence of Amino acids also differs between spelt and wheat, spelt containing more cystine, isoleucine, leucine, methionine and neurotransmitters, phenylalanine and tryptophan. Because it yields less and each individual grain of spelt, unlike common wheat, is covered by a tough, tenacious outer husk which requires removal before being milled into flour, I would go with a durum type wheat like the Khorasan wheat that I grow, Kamut, which is, in fact, an ancient type of durum wheat.