If you use Markdown formatting in your MLO notes (which you can enable and disable via Tools --> Options --> Appearance), then typing a hyphen and space at the start of the line ("- ") will render as a bullet in view mode. However, many people don't like the complication of having to switch between view and edit modes in your notes to be able to see the Markdown formatting.
Another alternative, if you have a numberpad on your keyboard (on some laptops it's shown as a coloured block of numbers, accessed by holding down the function key), then you can write any character down by holding Alt and typing it's ASCII code. For a bullet point, you'd need to hold down (laptop Fn key +) Alt and type "0149" on the keypad.
(For another example: The accented é in my name is Alt+130 on the numberpad)
Stéphane