You can use the IDE or the command line tools to compile programs for a 64-bit environment.
In the Visual Studio IDE, you set your platform target to 64-bit prior to compilation by choosing x64 in Platform target on the COBOL page of your project settings.
You can also compile from the command line by using the 64-bit Command Line Tool that is supplied with your product. You use the same compilation syntax as you would to produce 32-bit output; see Compiling from the Command Line (Windows) for more information.