if you are planning to root a device and wanted to know if it is possible, you should always start out over at
https://forum.xda-developers.com/. it is a developers forum where the developers publish their root methods, custom recoveries, custom roms, and other root related goodies. if you do not find a forum for your device then that usually means that there is no dev community supporting it. just remember no devs=no fun. and that usually means that there is no root method for your device.
keep an eye out on this thread:
https://forum.xda-developers.com/android/help/help-rooting-coolpad-legacy-3705a-info-t3952579/page7