Visit sites that specialize in SPD firmware. You will need to search by the Model Name or the "1H10" code.
The search term "sp7731e+1h10+native+firmware+link" a specific firmware build for mobile devices using the Spreadtrum (Unisoc) SC7731E sp7731e+1h10+native+firmware+link
If the tool hangs at the beginning, your USB drivers are likely broken or unsigned. Re-install the SPD drivers using "Disable Driver Signature Enforcement" mode in Windows. Visit sites that specialize in SPD firmware
Once finished, the progress bar will turn green and display a message. or enter bootloader mode.
The device will not power on, charge, or enter bootloader mode.