Why do different proteins have their amino acids in different orders

It is understood that not all them have the same function because the shape dictates function.

Explanation:y

All the amino acids of the proteins are categorized under three groups, because side groups of each amino acids differ from others.

It should be noted that the sequence of amino acids in a protein is based on the nucleotides sequence in the gene that is encoding it. This now determines the function of the protein.