Yeah. I won’t play DND because it’s too open ended. I simply don’t want to commit that much time to a campaign.
But there are board games like Mansions of Madness that use an iPad as DM. You can play as many or as little of the scenarios you want. Then DM later if you get into it.
There are also sandbox type board games. There is no DM but you get to decide what you want to do.