Let me clarify the meaning of this term first.
Select the element in which we are going to apply Superscripts and select the same then go to google docs toolbar and select Format Tab there, After that select the Text option, Then click on Superscripts.
Insert The Superscript Form Google Docs Tools
Go to Google docs tools and select Insert Tab, then click on Special Character option, Select the Superscripts option form appeared tab.
Above are the detailed explanation about Superscripts. we can follow the same process to apply the Subscripts in google docs.