Plug the power back in. The device should automatically begin the upgrade process.
To ensure you are downloading a genuine, "full" firmware package that won't brick your device, you should follow the official protocol: evpad 5s firmware download full
If you have received the firmware files (typically an .img file) from official support, the general restoration process is as follows: Plug the power back in
If your device is still functional and you are simply looking for system updates or the core "Venus" application suite, these official portals are commonly used: these official portals are commonly used: