I don't know about bookmarks, but in LO writer, inserting fields is:
Insert -> Fields -> (choose a field, or "other..." and choose lots more)

It does a lot more than early Word for Windows, but some of the features are hard to find and hard to work out from the documentation. I'm not sure that MS office is all that much easier, except that if you ask around it doesn't take so long to find someone who knows the answer (usually someone at the next desk)... but there are some online forums where you can get help from other OO/LO users.

There are more training courses in MS products too. My wife went on training courses for Excel when she was in an admin job, and now when she uses Open Office she complains that it can't do various simple things, but of course it can - you just have to press different keys or find a different menu or mouse gesture from the one you were trained to do with Excel.