This PowerShell script will deploy a new root forest with a forest and domain level of Windows Server 2012 R2.
Import-Module ADDSDeployment Install-ADDSForest ` -CreateDnsDelegation:$false ` -DatabasePath "C:\Windows\NTDS" ` -DomainMode "Win2012R2" ` -DomainName "test.local" ` -DomainNetbiosName "TEST" ` -ForestMode "Win2012R2" ` -InstallDns:$true ` -LogPath "C:\Windows\NTDS" ` -NoRebootOnCompletion:$false ` -SysvolPath "C:\Windows\SYSVOL" ` -Force:$true