(but of course, on the same line). Word will allow me to either put superscript or subscript, but not both. Putting a superscript a and then a subscript b kinda works, but it leaves a space that is ...

Use Alt codes on Windows to type exponents, like Alt + 0178 for superscript 2. On Mac, use the Baseline format in apps like Pages to add superscripts for exponents. Use Text Replacement on iPhones to ...