: Scroll down and select Device Preferences or General .
: Select System Update . If the TV is connected to Wi-Fi, it will check for available versions and offer a download option if an update exists. Manual Installation via USB Download Mitashi MiDE065v22 Firmware part1 rar
If your TV will not boot or you must use a downloaded .rar file (like the one you mentioned), follow these general steps: How to update the software on an Android TV - TCL Support : Scroll down and select Device Preferences or General
: Select the About section to view system information. Download Mitashi MiDE065v22 Firmware part1 rar
The safest way to get the latest official software is through the TV's built-in update tool: