You already learned that 披露 means "announcement" or "display," so add a banquet to that and you're at a wedding reception! Or if no one's getting married but they're showing off something at a big place with food and stuff it's a just a normal reception.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
Please teach me manners for when I attend my friend’s wedding reception.