A new question from an old Techno-dolt: I have an OLD Ipad which runs iOS 9.3.5. The Room: Old Sins requires iOS 10.0. Given that I have no clue what those letters and numbers mean, is there a way I can purchase/download/install the upgraded iOS and then play the new game?

It depends on how "OLD" your iPad is.
The current version of iOS is 11
If your iPad is too old, installing iOS 11 on it will make it crawl, and forget about playing any games on it.

Unless your iPad is relatively recent, I suggest you wait until The Room: Old Sins is made for PC -- or consider buying a new iPad if you have money to burn.

This site may help you figure out how old your iPad is
https://www.macworld.co.uk/how-to/ipad/how-identify-which-ipad-you-have-3528437/

Once you have the model or year, you can check how well that model works with the current iOS 11.

Jenny100: Thank You. According to the info "it's a bit of a golden oldie." (Sigh) That might explain why my Grandson asks if I have to wind it up at night. Anyway; Thanks.