$ sudo apt-get update
$ sudo apt-get install ocaml-native-compilers 

ocaml-native-compilers is installed in your system.

Make ensure the ocaml-native-compilers package were installed using the commands given below,

$ sudo dpkg-query -l | grep ocaml-native-compilers *

You will get with ocaml-native-compilers package name, version, architecture and description in a table

ocaml-native-compilers package basic information: