Does searching the settings for “OTG” yield anything? I seem to recall it can be labelled a bit differently across the versions.
USB OTG Checker can also be installed to verify whether it is available and enabled - https://play.google.com/store/apps/details?id=com.faitaujapon.otg
Failing that, try the official Huwawei OTG cable for your device - they shouldn’t be expensive. An OTG cable is not the same as a regular USB cable. If still no joy, it might just be that this device is incompatible…