If you decide to proceed, perform these checks to minimize the risk of a permanent "brick":

Firmware4Mobile is a third-party repository. It is not an official Infinix or Google source. ⚠️ Safety Assessment Risk Level: High

You cannot flash "Root" files unless your bootloader is already unlocked (this wipes all data).

If the firmware version (V686) does not exactly match your current build version, flashing this file can "brick" your device (rendering it unusable).

Instead of downloading pre-made .rar files from the internet, the to root an Infinix X663 Download the Official Stock ROM for your specific build. Extract the boot.img yourself. Patch it using the Magisk App on your phone. Flash the patched file via Fastboot on a PC.

Rooting and unlocking the bootloader immediately voids most manufacturer warranties.