Your NodeMCU gets an IP and if you use the Serial Monitor in the Arduino IDE then you’d know what to plug into the Device configuration in ST.
The step you’re missing is where everybody gets stuck when first playing with ST. See one of my first posts in this forum.
The key is to add the code under ST IDE > Device Handlers then create a brand new device under ST > Devices and in one of the drop-downs you have to scroll to the bottom to see your CUSTOM/NEW Device Handler. In the required address field feel free to use some junk because I manipulate it at runtime anyway to be correct per the CONFIGURATION that you do in the ST Mobile App.