@Marido: I'm not sure if it's possible to utilise both your Wi-Fi and Mobile Data connections simultaneously, as this feature seems to refer to faster switching between networks. You may wish to head to Settings > Connections > Wi-Fi > Tap the 3 dots in the top right > Advanced > Switch to mobile data, and toggle this option OFF, so your Note 10 doesn't prioritise your Wi-Fi connection. You should also make sure that your Mobile Data is active by heading to Settings > Connections > Data usage > Mobile data > On. Let me know if this helps.
Well I don't how to tell you this but my old android can use both mobile data and WiFi. boost my internet connection and play game more smooth. If I turn both of them on it should be like this.