The microwave will stop automatically when using certain features like pre-programmed recipes or thawing functions. However, for manual cooking, you need to set the time and press start; it will beep when the time is up. For specific automatic stop features, refer to the user manual for detailed instructions on each function.
Yes, according to the manual German page 19
Press the Child Lock and STOP/ECO buttons simultaneously.
No signal tones are emitted when a function is terminated
I have not tried this out myself. According to the text, the signal tones are switched off when a function is ended.
I have not checked whether the tones are then also switched off when setting.