How to connect device to openhab2

Setup, Configuration and Use Beginners
1

Hi,
recently i installed OH2 with mosquitto on my raspberry pi 3 b+ and i configured everything and i programed my nodeMCU with sonoff code and got it to connect to the mqtt broker.
My question is how can i add the device to openhab and make a switch so i can turn it on and off?

2

https://docs.openhab.org/v2.1/tutorials/demo.html

3

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