XAMPP SSL Tutorial https://shellcreeper.com/?p=2573

make-cert.bat

@echo off
set /p domain="Enter Domain: "
set OPENSSL_CONF=../conf/openssl.cnf

if not exist .\%domain% mkdir .\%domain%

..\bin\openssl req -config cert.conf -new -sha256 -newkey rsa:2048 -nodes -keyout %domain%\server.key -x509 -days 3650 -out %domain%\server.crt

echo.
echo -----
echo The certificate was provided.
echo.
pause

where cert.conf came from ?

cert.conf is created in this article which the script is based on: https://shellcreeper.com/how-to-create-valid-ssl-in-localhost-for-xampp/