Main components is a Google system app that's installed by default on many different brands of devices, including Samsung and Xiaomi. The main function of the app is to assist in downloading security updates for the operating system, so it's best not to uninstall it. Similarly, it's not recommended to install the app unless your device is running Android 13 or higher and you know exactly what you're doing.
Some users have reported that removing Main components (com.google.mainline.adservices) has allowed them to fix problems downloading and installing updates for Google Play. It's true that, at times, this app may conflict with other system apps. That said, as with all system apps, you should only remove it if you know what you're doing and are willing to assume that if something goes wrong, you'll have to reset your device to factory settings.
Sometimes, in an attempt to increase the available space on a device's memory, or to reduce RAM consumption, you might delete apps you think are useless. So, if you've deleted the app by mistake or simply want to force its update, download Main components's APK. After installation, your device should work normally again, and you should be able to receive security updates without a problem.
