It is not possible, only MikroTik CRS devices with RouterOS and SwitchOS systems can be used as a router or as a switch but not both at the same time. 

These devices are designed to handle a large amount of traffic and offer diverse functionality, making them suitable for a wide range of network applications.

As a Router

MikroTik CCRs are primarily routers, equipped with RouterOS that offers advanced routing functionalities. This includes, among other features:

• Dynamic routing through protocols such as OSPF, BGP, and MPLS.
• Firewall, with advanced capabilities for packet filtering and security.
• VPN, supporting multiple protocols to establish secure connections.
• QoS, to manage and prioritize network traffic.

These features make them ideal for use in environments where it is required to manage traffic efficiently, provide advanced security and connect different network segments.

Like Bridge

Although MikroTik CCRs are not dedicated switches, it is possible to configure some of their interfaces to act as switch ports, using the bridge mode from RouterOS. This allows several physical interfaces to be grouped into a single network segment, functioning similar to a switch:

• Bridge Creation: You can combine multiple Ethernet interfaces into a bridge, which acts as a software switch, allowing connected devices to communicate with each other as if they were in the same broadcast domain.
• Performance: While software bridging may not offer the same performance as a dedicated switch, CCRs are equipped with powerful CPUs that can handle a considerable volume of traffic efficiently. Some CCR models include specific hardware to speed up bridging, although this performance may vary depending on the model and specific configuration.

Considerations

While a CCR can perform both functions to some extent, it is important to note that a dedicated switch could be more efficient in terms of performance for switching tasks, especially in high-density or high-performance environments.

The decision to use a CCR as a router, bridge, or both will depend on your specific network needs, budget, and the anticipated workload of the device.