@Farrokh everything you imply or ask about how the script works is not tied to the script itself, it's just how the game works
Scripts don't somehow check for their filenames, the game handles loading scripts, any script in the scripts folder is loaded, no reason to have name checks for files
Scripts cannot permanently change dvar values in the game. You could potentially have a more complex system now with the recent Plutonium updates that reads another file but it's not really needed in my opinion
If you want to have dvars set when starting your game then you can edit the game's CFG (assuming we're talking about private games), or yeah edit the script
Permanently save dvars values
Press Win + R, paste %localappdata%\Plutonium\storage\iw5\players\config_mp.cfg
If asked how to open it use Notepad (or any text editor)
Go at the very bottom of the file and add seta dvar_name dvar_value
Change dvar_name and dvar_value with the corresponding values
For example seta g_speed "800"
This also works for any custom dvar created by a script or any other source