%* in batch file mean all command line arguments?
Yes. According to the official Microsoft documentation:
The %* batch parameter is a wildcard reference to all the arguments, not including %0, that are passed to the batch file.
Besides this, a comment by @kobkira notes that you can take only up to 9 arguments in conventional syntax. Like this if you want to get n number of arguments in separate array style variables, use this syntax:
@echo off & setlocal enabledelayedexpansion & set "n=30" for /l %%a in (1,1,%n%) do ( for /f "tokens=%%a delims= " %%b in ('echo %*') do ( set "arg[%%~a]=%%~b" ) )