The sudo should not be automated. So it's difficult do.

You can start here:
https://beta.winscp.net/eng/docs/faq_su

I don't have the knowledge to make a poweroff .bat to poweroff my nas. Becouse the issue the root is now more safe and you need a sudo statement to reach it. Can You help me with that?

What is the question?

Since the update version 6 and above from DSM Synology you need root permission for the command poweroff. How can I make a .bat file with this purpose? :)