“وَ” (wa)a joining word meaning “and.” It connects this word to what came before.Corpus grammarCONJ — prefixed conjunction wa (and).
“جَنَّٰتٍ” (jannātin)means “And gardens” in this verse. It is a noun. a naming word. Here it is feminine — plural, not specific, genitive.Corpus grammarN — feminine plural genitive indefinite noun.