Yes, amino acids are what make up proteins. Amino acids are assembled via peptide bonds in order to form specific proteins. Protein is digested when the peptide bonds are broken. At that point the amino acids are available.
Not all proteins are alike, though. A complete protein is a protein that contains all ten essential amino acids. Those are the ten that cannot be synthesized by the human body. Therefore, they must be obtained through diet.
Meats, poultry, eggs, fish and milk are all complete proteins.