You could buy the ad-free version from the Microsoft Store. Microsoft Solitaire has been gone since Windows 8.1 came out. It was not pulled via Windows 10.
The Microsoft Solitaire Collection provides some outstanding solitaire games. But there are more "basic" versions in the store too.
Try Simple Solitaire which is free and has no ads.
(Well, no overly OBTRUSIVE ads...less distracting than what they stick us with in Outlook Mail, anyway).
It's pretty much the same solitaire game you used to have.