@echo off
for /F "eol=| delims=" %%I in ('dir * /AD /B /O-D 2^>nul') do cd "%%I" & goto DoneCD
echo No subdirectory found in: "%CD%"
:DoneCD

C:WindowsSystem32cmd.exe /c dir * /AD /B /O-D 2>nul

set "DoneCD=" & (@for /F "eol=| delims=" %I in ('dir * /AD /B /O-D 2^>nul') do @if not defined DoneCD cd "%I" & set "DoneCD=1") & set "DoneCD="

@set "DoneCD=" & (@for /F "eol=| delims=" %%I in ('dir * /AD /B /O-D 2^>nul') do @if not defined DoneCD cd "%%I" & set "DoneCD=1") & set "DoneCD="

@echo off
set "DoneCD="
for /F "eol=| delims=" %%I in ('dir * /AD /B /O-D 2^>nul') do (
    if not defined DoneCD (
        cd "%%I"
        set "DoneCD=1"
    )
)
if not defined DoneCD echo No subdirectory found in: "%CD%"
set "DoneCD="