Restoring without an external restore image -might- be possible, IF the internal recovery image is still ok. From OFF, press and hold the power and volume down buttons. A recovery menu will appear. This is where you diagnose troubles, restore from the internal recovery image, or boot from UEFI Installer.
On mine, reinstalling from the internal recovery solved the reboot loop, but everything was too slow to use, so I performed a fresh install of Windows 10-1909 (32-Bit). I had to use Rufus to make a compatible USB installer, as the Microsoft media creator kept creating an NTFS partition on the install media, which does not work with Secure Boot. See USB media creation below:
1) Obtain a current Windows 10 (32-Bit) ISO file.
2) Within Rufus…
Image Option = Standard Windows Installation
Partition Scheme = GPT
Target System = UEFI (non CSM)
File System = FAT32
3) Boot your tablet from this by powering on and holding POWER and VOLUME DOWN buttons.
Unfortunately, I don’t have the driver installer.
I did however use Driver Magician to “backup” the drivers, but screen auto-rotation does not work and thermal sensor drivers refuse to reinstall from the driver files. Everything seems to work otherwise.
Beware the many, many useless and frequently infected “Driver Packs” out there.
The manufacturer, both US (NextBookUSA) and foreign (yifangdigital.com) have been unwilling to provide drivers.