If you just want the text, then you can just type it in as the capital
letters for i, v, x, l, etc. If you want to make a paragraph a numbered with
Roman Numerals, then select which paragraphs you want to apply this
formatting to, and choose Format menu, Bullets and Numbering, and then choose
the Numbered tab and click on the Customize button at the bottom of that
window. Then, under Number Style, you can choose Roman Numerals, or any type
of number that you want to number each paragraph. Is that what you needed?

How do I insert Roman Numeral