What do you mean? You can edit a PDF and enter whatever you want into it... There are no language-specific editing tools.
As for spell-checking: If you have the Spanish dictionary installed in Acrobat then you can use it, yes, but keep in mind that the built-in spell-checker only works with comments and form fields. If you want to check the static text of the file then you can use a script, like this one I've developed: Custom-made Adobe Scripts: Acrobat -- Spell Check Suite