Is BulkCopy available for SQL-Server 2012 Is BulkCopy still supported by SQL-Server 2012?
Yes, BCP.EXE for SQL Server 2012 works on Windows 10. I have tried it myself several times, though do not use it extensively (so there could be a minor issue with one of the features that I haven't used, but I highly doubt it).

Also, BCP (like the other command-line utilities) is freely available, so you should test it for yourself on your system(s). You can download it from the following page:

Microsoft® SQL Server® 2012 Feature Pack

Expand the "Install Instructions" section and scroll down to (or search for) "Microsoft® SQL Server® 2012 Command Line Utilities".