The stock TCL software includes a built-in backup tool for settings, Wi-Fi passwords, and app data. For a full firmware backup, you need a custom recovery like TWRP (not available for all TCL 50 5G variants).
It is highly recommended to back up your phone's memory before starting a firmware update to prevent data loss. firmware tcl 50 5g link
Ensure you have a stable network connection. Charge Device: Make sure your battery is at least 30%. The stock TCL software includes a built-in backup