How do enzymes and substrates work together?

Google this exact same question, you'll find many different answers

Other enzymes help bind two molecules together to produce a new molecule. Enzymes are highly selective catalysts, meaning that each enzyme only speeds up a specific reaction. The molecules that an enzyme works with are called substrates. The substrates bind to a region on the enzyme called the active site.

OR

Another explanation could also be: A simple explanation is that the substrate molecule(s) "fits" into a specific area of the enzyme molecule (active site). This forms an enzyme-substrate complex; the substrate molecule(s) is changed during its interaction with the enzyme molecule.