Answer 1

You can limit the router's download and upload speeds by enabling and configuring QoS (Quality of service). The QoS section can be found in Services → QoS. From there you can select download/upload speeds (bit/s) for specific interfaces. 

You can find more detailed information on QoS here

Comments

Is there a feature in which we can set a schedule, like a time period, where QoS activated/deactivates?