End result will be the PNG below, but when I use StringJoin to join Styled Characters, error pop up StringJoin::string: String expected at position 1 in StringJoin[M]. Possible issue is StringJoin works only with explicit strings, while TreeForm[Style[“M”,Red]] shows it is not a String and thus cannot use StringJoin, how could I make it?
There is no PNG file in your post. Try adding it.
Use Row to join non-string characters:
Row[{Subscript["C", 6], Subscript[Style["H", Blue], 14]}]
