My sonyDSC WX350 will not download any pictures with on without the lead to my 125 iPad Pro

USB Mass storage mode is the correct mode to use with an iPad.

What iPad year and model are you trying to to use this camera with?

Make your iPad is already in the Photos app when doing the transfer.

Are you using any proper Apple adapters with your iPad?

What iPad year and model do you have/own?

That iPad Pro model is almost as old as mine.

I am also familiar with many Sony digital cameras

Did your Sony camera come with a cable with an Apple Lightning connector end?

Most Sony cameras do not come with such a cable.

You need to purchase Apple’s Lightning camera adapter to use with that old an iPad.

Either this one

https://www.apple.com/shop/product/MD821AM/A/lightning-to-usb-camera-adapter

OR

This one

htthttps://www.apple.com/shop/product/MD820AM/A/lightning-to-micro-usb-adapter

AND/OR

if your camera has a compatible card, maybe this one, as well.

https://www.apple.com/shop/product/MJYT2AM/A/lightning-to-sd-card-camera-reader

And maybe, perhaps, this one, as an additional purchase adapter, with any of the other Apple adapters I have listed, as well.

https://www.apple.com/shop/product/MD820AM/A/lightning-to-micro-usb-adapter

Best of Luck to You!

You may need to use an Apple camera adapter and you need to make sure the camera is in a mode to allow the iPad to import the pictures.

Cameras that transfer pictures wirelessly to other wireless devices, may not work with Apple iOS/iPadOS devices.

To import/transfer picture from a digital camera to iPad/iPhone may require a hardwired connection to do so.

Best of Luck to You!

FYI,

You have signed up into a, largely, volunteer Apple product user to user technical support community.

Most everyone that responds here, responds and helps here on a volunteer basis.

User help comes when it comes.

So, you have to have patience and may need to wait some time before getting any responses to your Apple product questions.

Sony has an entire guide published at https://support.d-imaging.sony.co.jp/www/disoft/int/playmemories-mobile/en/operation/dsc_send_ios.html