“وَ” (wa)a joining word meaning “and.” It connects this word to what came before.Corpus grammarCONJ — prefixed conjunction wa (and).
“نُيَسِّرُ” (nuyassiru)means “And We will ease you” in this verse. It is a verb. an action or state word. Here it is imperfect verb, verb pattern two.Corpus grammarV — first person plural imperfect verb.
“كَ” (ka)an attached pronoun meaning “you” when speaking to one man.Corpus grammarPRON — second person masculine singular attached pronoun.