What is the next step in the process after a substrate enters the active site of an enzyme?

I think the answer is : The enzyme and the substrate bind to form the enzyme-substrate complex :))
i hope this be helpful 

Enzymes are biocatalysts which increases the rate of the biochemical reaction by lowering the activation energy of the reaction.

It performs the catalysis in four steps:

The substrate enters the active site of a specific enzyme. It forms the enzyme-substrate complex with the help of non-covalent interactions such as complementary shape, hydrophobic interactions, hydrogen bonding et cetera. The process of catalysis takes place during which old bonds are broken or rearrange to convert the substrate into the product. It results in the formation of enzyme-product complex. The product has different properties as compared to the substrate due to which it gets released from the active site of the enzyme. The enzyme is ready to bind to a new substrate.

Thus, the correct answer would be the formation of the enzyme-substrate complex.

Many archeologists and anthropologists disagree with dr. thorne's view.  thorne strongly believes that what many calls "homo erectus"  was in fact  homo sapiens,  and that they migrated out of africa almost 2 million years ago and dispersed throughout europe and asia. that's way different  from what scientists have always believed about the evolution of the species.