Iran is still a long way from having an operable nuke. That would require testing and developing a delivery system. And even after doing all that they would be unlikely to penetrate Israel’s iron dome defense system. Seeing as to how Israel has hundreds of nukes they would retaliate with there’s no way Iran would launch such an attack. The Mullahs are not suicidal themselves contrary to what some may believe they only encourage that in their followers.
What makes you think Iran “needs” a missile to deliver their Nuke to Israel? Small truck may be way more effective.