Can't connect pi4 with my pc and my pc as broker

[ZEus]

Hello everyone im new to node-red . Im trying to connect a plc s7-1200 with pi4 using mqtt ( mosquitto) and setting up my pc as a broker so the problem is my pi4 can't connect with my pc when activating node red in terminal (1883 port) and when i tried to ping the pi4 it's unsuccessful. i followed a youtube tutorial here is the link : communication between Raspberry PI and PLC S7 1200 using MQTT - YouTube
ps:in the video he opened node red in his pc and i couldn't do that only in pi4
please if you have any ideas let me know ill be appreciated

[jbudd]

It seems odd to install Mosquitto on a PC if you have a Raspberry Pi4 with Node-red on it.

It's simple and very reliable to install Mosquitto on a Pi and you can guarantee that MQTT messages will continue to flow even if the PC is turned off.
The MQTT broker should have a static IP and Mosquitto has to be configured to allow connections from other devices.

@ZEus

the problem is my pi4 can't connect with my pc when activating node red in terminal (1883 port) and when i tried to ping the pi4 it's unsuccessful.

If you can't ping the Pi, can you see it on the network? IpScan24 on the PC is a good tool for this.
What does the ifconfig command on the Pi show?