Hi KathieParish,
Good day! I’m Jhakesong and I'll try to help you today.
I am afraid windows 11 has combined all the solitaire games in one collection called Microsoft Solitaire Collection. You can find it when you click Search and type Solitaire.
When you open the app, go to Solitaire Collection. Then you will see the solitaire modes that you used to play like Free Cell and Spider. They still have an Undo feature that allows you to go back when you make a mistake.
It's just combined into one icon which is Solitare & Casual games inside windows. But when you launch the app they are separate from each other.
Let me know how it goes. Have a great day!