Well there are a lot of chemical substance that we need in order to live and grow.
We need proteins since they are polymers of amino acids and are building blocks of bodies. Most proteins are enzymes and enzymes are catalysts that helps speed up chemical reactions inside our body ( for ex providing milk digesting products that helps us digest milk when we drink it; if we don’t have the enzyme to make the product then thats called lactose intolerant.
We need lipids since they are used to make part of cell membranes. They are also used for storing energy and releasing energy when we need it. Cholesterol and other lipids helps sexual development, reproductive system, ability to respond to stress, etc.
Nucleic acids are found in the DNA and RNA and provides instructions step by step on how to make proteins.
We also need vitamins, water, and lots of other chemical substances.