bash <(curl -sL https://raw.githubusercontent.com/node-red/linux-installers/master/deb/update-nodejs-and-nodered)


Press Enter to create a Node-RED Settings file on /home/pi/.node-red/settings.js
Do you want to set up user security? Yes.
Enter a username and press Enter (you need to remember it later).
Enter a password and press Enter (you need to remember it later).
Then, you need to define user permissions. We’ll set full access, make sure the full access option is highlighted in blue and press Enter.
You can add other users with different permissions if you want. We’ll just create one user for now. You can always add other users later.
Do you want to enable the Projects feature? No.
Enter a name for your flows file. Press Enter to select the default name flows.json.
Provide a passphrase to encrypt your credentials file. Learn more about what is a passphrase.
Select a theme for the editor. Simply press Enter to select default.
Press Enter again to select the default text editor.
Allow Function nodes to load external modules? Yes.
Node-RED configuration was successful. All settings are saved on settings.js.



after complete installation

node-red-start