Once you have your and the ROM zip file, follow these steps carefully.
If you need to unbrick your device or return to factory settings, you can download the official firmware for models like the XT2173-1 or XT2173-3 from MotoStockROM or AndroidFileHost . motorola g31 custom rom link
For the Motorola G31, ArrowOS currently offers the best balance of performance and battery life. Visit the XDA forum for the specific "ArrowOS rhone" thread to get the direct download link. Once you have your and the ROM zip