Please how can I simulate a zigbee wireless sensor network in omnet++ with a total of 30 nodes. I'm new to omnet++. I'm using omnet 6 Below is my network file.

package projtest4.simulations;

import projtest4.ZigbCoordinator;
import projtest4.ZigbRouter;
import projtest4.ZigbEndDevice;
import projtest4.ZigbPhy;
import projtest4.ZigbMac;
import projtest4.ZigbNet;
import projtest4.ZigbApp;

network ZigbNetwork
{
    submodules:
        coordinator: ZigbCoordinator;
        router1: ZigbRouter {
            @display("p=127,64");
        }
        router2: ZigbRouter {
            @display("p=230,76");
        }
        endDevice1: ZigbEndDevice {
            @display("p=364,27");
        }
        endDevice2: ZigbEndDevice {
            @display("p=348,175");
        }
        phy: ZigbPhy {
            @display("p=318,206");
        }
        mac: ZigbMac {
            @display("p=371,256");
        }
        net: ZigbNet {
            @display("p=421,302");
        }
        app: ZigbApp {
            @display("p=460,359");
        }

    connections:
        coordinator.out --> router1.in;
        router1.out --> router2.in;
        router2.out --> endDevice1.in;
        router2.out --> endDevice2.in;

        mac.out --> phy.in;
        phy.out --> mac.in;
        net.out --> mac.in;
        mac.out --> net.in;
        app.out --> net.in;
        net.out --> app.in;
}`

I have defined the modules imported by myself. Below is an example of a module I created

simple ZigbMac
{
     parameters:
        @display("i=device/antenna");
    gates:
        input in;
        output out;
}

Please I also need to understand what to do here (error in omnrt++)

src/Makefile does not exist. Please use "make makefiles" to generate it!