To run Julia, you need to load the module first:

module load julia

The general code to use a package in Julia is: :

using Package_Name

The general code to install a package in Julia is: :

using Pkg
Pkg.add("Package Name")

Install JuMP Package:

Pkg.add("JuMP")

Install CPLEX package: First add path to cplex binaries

ENV["CPLEX_STUDIO_BINARIES"] = "/home/ibm/cplex-studio/12.9.0.0/cplex/bin/x86-64_linux"
Pkg.add("CPLEX")
Pkg.build("CPLEX")   

using Pkg
Pkg.status()  
Pkg.installed()