Getting started with CLI on RaspberryPi

Gordon,
I have run that line of code but have since reinstalled espurino so will do it again tonight.
Also sudo hcitool lescan is finding Bluetooth devices including Pucks so I am confident that the Pi 3 hardware is OK.
I can see that there is lots of reference information here about the API and a number of example code snippits. Maybe I have missed something but what I haven't found and feel may be missing is some fundamentals about how I will then be able to interact with these pucks through the CLI. The detail will of course depend on what I want to do but as a starter for 10 I would like to be able to do some simple things like:

• Connect to a puck and Disconnect
  
• Check the battery level interactively
  
• Activate LEDs interactively
  
• Upload a simple code module to for example make LED flash in response to button press
  
  

Thanks in advance
James