The iCab Mobile app will allow uploading of files to most sites. Whether it will work with the specific sites you need, no way to tell without trying. The document must first be copied to the iCab Mobile app (using Open In or some other method) before it can be uploaded to a site.
iCab Mobile is one of the most versatile third party web browsers available for the iPad.
The IPad Forum is a community of members from all walks of life and from all over the world coming together to share our experiences and to help each other learn about this wonderful piece of technology the Ipad. There is a wealth of information already here in the many threads we have so doing some searches will answer most of the questions you have. If then you cannot find the answer you are seeking then by all means post your question. There are many friendly and informed members here only too willing to help you.