After the mobile phone is plugged into the computer, right-click the device manager of the computer, and there is a "port" in it. If there is such a thing under the port, you can open the brush.
(Not necessarily this name, something similar will do. Or appear after plugging in the phone)
Download MiFlash, line brush package and corresponding driver first. Restart the computer, disable driver signature enforcement "and then you can open the brush.
Useful brush driver, MiFlash and brush method are all in the attachment.
If you don't want to download, you can leave a QQ and I'll send it to you.