How to subscript/superscript single character in Text Edit?

I would like to know how to subscript/superscript "single" character in Text Edit. I have followed this question: Entering superscript text (exponents) in TextEdit?, which is format-font-baseline-Subscript but it subscripts/superscripts single line, even if I highlight single character. I tried to use different fonts, but it seems like I cannot select single character and then subscript/superscript it. Thank you for every answer.