starting on Q# : check out: https://docs.microsoft.com/en-us/quantum/quickstart?view=qsharp-preview&tabs=tabid-vscode

Q# is a programming language for quantum computing. Q# draws on inspiration from F# as a functional language, C# for syntax, and draws some ideas from Python.

A Q# operation is a callable routine, which contains Q# code to carry out a quantum operation. An operation is the basic unit of quantum execution in Q#.  It returns a single value as output, specified after a colon, and may be a tuple.

A Q# Function is classical subroutine used within a Quantum algorithm and can only contain classical code.  A function will  take a single value as input and returns a single value as output.

namespace Quantum.HelloWorld

{

    open Microsoft.Quantum.Canon;

    open Microsoft.Quantum.Primitive;

    operation SayHello () : Unit {

        Message("Hello World!");

    }

}