Onn Tablet: Stuck on Fastboot Mode? Easy Fix

Can I change the Boot Slot from Fastboot with a command? change slot fastboot Change CSC with one click; Remove FRP for new security patch Auto-detect file and select slot; Auto-extract for ZIP file; Ignore MD5 change slot fastboot recovery mode that shows signal strength and IMEI No They showed as having a uSD slot, so hopefully they have the correct chipset

bom slot i do the fastboot with command my phone reboot : black screen with only and stays like that : => FASTBOOT mode then i command fastboot