Sean Penn didn't say unvaccinated people need to go to jail. The claim's based on 2 articles - one from NewsPunch, and the other from The Gateway Pundit. Both are well-known fake news/disinformation sites (believed by morons). What he really said is here:
Sean Penn says unvaccinated need to go to jail 😂
I don’t even like cancel culture… I’m deadly against it… but, can we cancel him please?! 😂