Here is a typical Config.nt (in both cases, you need to remove REM from the lines that you want to apply):
REM Windows MS-DOS Startup File
REM
REM CONFIG.SYS vs CONFIG.NT
REM CONFIG.SYS is not used to initialize the MS-DOS environment.
REM CONFIG.NT is used to initialize the MS-DOS environment unless a
REM different startup file is specified in an application's PIF.
REM
REM ECHOCONFIG
REM By default, no information is displayed when the MS-DOS environment
REM is initialized. To display CONFIG.NT/AUTOEXEC.NT information, add
REM the command echoconfig to CONFIG.NT or other startup file.
REM
REM NTCMDPROMPT
REM When you return to the command prompt from a TSR or while running an
REM MS-DOS-based application, Windows runs COMMAND.COM. This allows the
REM TSR to remain active. To run CMD.EXE, the Windows command prompt,
REM rather than COMMAND.COM, add the command ntcmdprompt to CONFIG.NT or
REM other startup file.
REM
REM DOSONLY
REM By default, you can start any type of application when running
REM COMMAND.COM. If you start an application other than an MS-DOS-based
REM application, any running TSR may be disrupted. To ensure that only
REM MS-DOS-based applications can be started, add the command dosonly to
REM CONFIG.NT or other startup file.
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