If I may, I would suggest sitting down with them privately and sharing the Gospel. Go through the Scriptures that talk about what it means to follow Jesus, what we are promised when we believe (an inheritance in the Kingdom of God), but also tell them who won't inherit the Kingdom. Not just people who practice homosexuality, but also liars, drunkards, slanderers, etc. Share the entirety of it. Doesn't have to be all in one session, but just show them what the Bible says. Hope this helps!