What "MI" Reset Usually Means
"MI" almost always refers to a device from Xiaomi's Mi / Redmi / POCO family — a phone, tablet, smart TV, or Mi Wi-Fi router. On every one of these, "resetting settings" means a factory reset: erasing user data, accounts, apps and custom configuration so the device returns to its out-of-the-box state. The exact menu path depends on the device class, but the logic is the same — find the reset option inside Settings, or use the hardware buttons when the device is locked, frozen or unreachable.
Before you begin, note that a factory reset is irreversible. It removes Wi-Fi passwords, Google or Mi accounts, installed apps, channel line-ups and picture settings. Sign-in credentials for Google or Mi accounts are worth noting down first, because some devices ask for the previous account after a reset to unlock.