multiple bullet points in an excel cell

Bartballon 

Unlike Word, Excel is not a real text processor. It doesn't have built-in support for inserting bullets.

So you'll have to insert a bullet in front of each line in a cell manually. You could insert one bullet, and copy the bullet and the space after it. You can then paste it in front of each line.

Or you could copy the following macro into a module in the Visual Basic Editor:

Sub AddBullets()
    Dim rng As Range
    Dim v() As String
    Dim i As Long
    Application.ScreenUpdating = False
    For Each rng In Selection
        v = Split(rng.Value, vbLf)
        For i = 0 To UBound(v)
            If Left(v(i), 1) <> Chr(149) Then
                v(i) = Chr(149) & " " & v(i)
            End If
        Next i
        rng.Value = Join(v, vbLf)
    Next rng
    Application.ScreenUpdating = True
End Sub

You can assign the macro to a Quick Access Toolbar button and/or a custom keyboard shortcut.

Save the workbook as a macro-enabled workbook and make sure that you allow macros when you open it.

If you want to use the macro in multiple workbooks, save it in your personal macro workbook PERSONAL.XLSB.

(See Excel Personal Macro Workbook | Save & Use Macros in All Workbooks for info about PERSONAL.XLSB)