When you use a Windows Server with Remote Desktop (RDP), you will not find a restart button on the START button. But don't worry, you can use the command prompt to restart. Here's how:
Please open the command prompt on your Windows server / vps. or you can type in the RUN menu using the CMD command.
After opening, to restart, you simply give the following command:
shutodwn /r
For other commands, you can see it by typing the command:
shutodwn /?