keyboard shortcut to rename the title of terminal? I have switched from Ubuntu to macOS (Sierra 10.12.5) recently and I am missing few very basic keyboard shortcut in the terminal. 

I used to open multiple terminal in tabs and set name of each tab  but couldn't find any keyboard shortcut so far, although I am using CMD + Shift + I which open the inspector window separately and there I can set the title name but again there is no way to close that inspector window using keyboard.

Kindly tell us if there any shortcut to do that?
You are almost there.

You can open the inspector to set the title name with CMD + Shift+I

In order to close it you can press ESC
 OR use the inspector toggle shortcut - CMD + I