Here's a step-by-step walkthrough on how to type in subscript and superscript in Notion
1. Type "/math" in the text area.
2. Choose "Inline equation" from the popup menu.
3. In the equation box, use underscores (_) for subscripts and circumflexes (^) for superscripts. Use parentheses ({})for the characters you want in superscript or subscript. Use Tilde (~) as your spacebar.
4. Click "Done".
Congrats! You have successfully typed in subscript and superscript in Notion!