How i can change lenguage of Calligra in spanish?

If you mean the language of the spellchecking, select the menu item "Settings"->"Spellcheck"->"Configure Spell Checking..." (That's at least what the menu entries are named in english). A dialogue will open with a combo-box at the top that allows you to select the default spellchecking language.
You probably need to install some spanish spell-checking-packages, I think Calligra uses hunspell.

If you mean the language of the application/user-interface itself, it should adapt to the systems language settings, as long as translations are available.

Actually the only language available to me in menu Help/Swith Application Language is "English". Too bad.

martinjean wrote:Actually the only language available to me in menu Help/Swith Application Language is "English". Too bad.

https://docs.kde.org/stable5/en/kde-wor ... index.html