Hey @max91,
the whole purpose of ngrok is expose your localhost to a public URL.
In other words, monday.com gets a connection to the machine you are running ngrok on.
First install ngrok.
Then open your console and enter:
ngrok http 3000
“HTTP” stands for the protocol you use and “3000” is the port you will expose by executing this command.
Next up your console will display something like this:
The HTTPS URL is the one you want to copy and paste/use.
Hope I could help you.
Greetings.