ZTE provides an Online Update feature within Settings > System > System Update . For those needing a fresh start or fixing software glitches, official Stock Firmware and manual offline update packages are typically available through the ZTE Support Portal . Core Strengths

If you tell me your exact (e.g., ZTE 8030XX) and the reason you need the firmware (boot loop, removing FRP, upgrading, downgrading), I can give you more precise download links and instructions.