In Windows 10, Advanced Output should be selected for connected screens. Mirroring is usually activated the first time the screen is connected. This can be easily switched with the key combination Windows+P.

Right mouse button on the desktop, display settings - there you can set everything and also drag the screens into the desired order (also press identify first to see which number is assigned to which display) so that the mouse moves correctly from left to right. Then select Multiple Displays - Extend desktop to this display. Then everything should be OK.