I can't see videos because I can't install adobe flash player. I read to enable plug ins, but I can't see either in my iPad.

You can't install plug-ins and flash is not supported on the iPad - and as Adobe have announced that they are stopping development on all mobile versions of it, it probably never will be.

Browser apps such as Skyfire, iSwifter, Puffin and Photon 'work' on some sites, but judging by their reviews not all sites. Also some websites, especially news sites, have their own apps in the App Store.

Depends what format they are in. Most YouTube videos posted to facebook work just fine, as do many others.

You can try using the'official' Facebook app or Friendly For Facebook - not sure whether they work with videos.