Alpha Numeric Outline of your required paper
This is the most common type of outline and usually instantly recognizable to most people. The formatting follows these characters, in this order:
Roman Numerals
Capitalized Letters
Arabic Numerals
Lowercase Letters
If the outline needs to subdivide beyond these divisions, use Arabic numerals inside parentheses and then lowercase letters inside parentheses.
https://owl.english.purdue.edu/media/pdf/20081113013048_544.pdf if you need to review alpha numeric outlines.