How Do I Download a PDF Document on iPad?

I save all my documents to the cloud, either through Microsoft OneDrive or Google Drive.

When I want to save a pdf document from the web on Google Drive or OneDrive, sometimes I am able to open it in Acrobat as a pdf and then proceed to upload it to the cloud.

But sometimes there is no option to open it in Acrobat. When this occurs, there seems to be no way to even download the document.

Can anyone tell me how to download a document to my iPad? I am using Chrome as my browser.

TIA!