This device was reset. To continue, sign in with a Google Account that was previously synced on this device. ? If you don't have his/her email and password, you need someone to do an FRP bypass to bypass the Factory Reset Protection that Google has implemented. I might know someone who can help.
For those who never learned Chinese (which are probably all of us on the English language site) I would recommend downloading 'Google Translate' App on your phone, you can then take a picture of the tablets screen, take said picture to the translate app and, you guessed it, it'll translate it for you. Tedious, yes but the"choose your language" section of new device setups are using located within the first few screens of the program. Hope that helps. 苹果糟糕