Concept of Kalimas is limited only to Indo-pak subcontinent.
Surah(complete surah or more than 3 short ayat or one long ayat) is what you recite in prayer.
I am hoping someone more knowledgeable than me can explain this properly.
Kalimah mean sentence. In example, kalimah shahada (sentence of shahada). While surah mean letter or document. In example, surah in Qur'an which formed from documented verses.
You can recite a complete short surah or few verses from long surah when you perform salah.