I have been trying to update my LinkedIn profile ( I am under a job search ) and didn't have a clue how to add bullet points in the experience section of the profile. Appears it takes ALT codes, so in the experience section you should be able to use any of the ALT codes ( I have tested with only a few ).

So press NumLock key to use the numeric keypad, then press and hold the ALT key while entering the numeric key code for the symbol you would like for bullet point using the keys on numpad.

A list of ALT codes can be found at https://www.alt-codes.net/