It's all about apps, or mostly so. Files go to apps, not the iPad in general. To use files you need a compatible app first, not as an afterthought. Apple only supplies built in apps for the most common (and not brand specific) file formats; then a few more apps of it's own for it's own stuff. After that you have to --->
Search the App Store for apps to do what you want. They will list in the features the various ways to import/export files. You should also search the forum (I recommend the custom Google Search at the top of the website) for subjects you are interested in. There a a ton of threads on printing, iCloud, and stuff you have not even thought to ask yet.
Here are some links to get you started.
[*]
AirPrint
[*]
Apple - iCloud - Your content. On all your devices.
[*]
Apple - iCloud - Learn how to set up iCloud on all your devices.
[*]
Microsoft Office itself is not available as an app, but you can use it either with a Remote Desktop app like Splashtop or LogMeIn; or a virtual desktop app like CloudOn or OnLive.
There are several Office Suite solutions that have varios degrees of utility and compatibility with MS Office. Research which one comes closest to what you need.
[*]The iWorks apps (Pages, Numbers, Keynote)
[*]Documents To Go
[*]Office HD
[*]QuickOffice
[*] Polar Office (new, but getting decent reviews)
As for Photoshop, Adobe Photoshop Touch is available in the App Store. There are dozens of other good to great drawing and photo manipulation apps available.