Iphone X and Ipad Pro crashed

Purchased new Ipad Pro in November. Started it by syncing to

my iphone X. Traveled to Asia bringing 3 devices, iphone x, old ipad pro, brand new ipad pro.

When I arrived at my destination the old ipad and iphone x crashed when i powered them up. All I got were spinning gears. called Apple, brought to authorized apple service centers, and still no results. other countries have different itunes than USA. Cannot reset devices purchased in USA.

Returned to USA. Tried downloading iTunes on my PC to reset my two devices. No can do. what’s next?