This post will assume you have Visual Studio installed with Microsoft Office 365 API tools for Visual Studio.
- Create a new Visual Studio project, lets say a console application.
- Press on your project the second mouse button and select “Manage NuGet Packages…”
- In the new window search for online packages and type in pnp or officedevpnpcore or similar. Then install the OfficeDevPnp.Core.Online package.
- Wait for the installation to complete. After this you are ready to use CSOM to operate on your desired O365 site.
As you can see from the image above the nuget package will install all of what you need. You do not have to worry about much. Easy, right :)?
Links to know: