how to automatically execute a .bat file

i'm really basic with comp stuff. im only in 9th grade but i wanna learn. i made a batch file with the commands

C:\WINDOWS\RUNDLL32.EXE user,exitwindows
exit

so when i click on the batch file, my computer shuts down. i want this batch file to run every time the computer is turned on. i call it perpetual off. except its not perpetual. yet. also i need help with sending files/text over a network and commands that close programs like explorer.

Ok for your first problem

in your autoexec.bat file type this
call c:\<batchfilename>


if you don't know how to get to autoexec.bat
in the command prompt go to the root of your C:
type dir you shouled see it.
type edit autoexec.bat then enter the above

second problem:

Here's a fun way to do this, go to your command prompt
type
start \\<computer name of file receiver >\c:$  this will take you to the coputers c: then just copy the file you want them to have.

Third problem:

well it depends from where you wanna close the program. From a dos prompt type exit <programname>