questions about soil and fertilizer

[rafiwinters]

Hi all, just joined (rejoined?) the group. Seeking thoughts or advice. There's a raised garden bed at the back of our yard and I was thinking of planting some stuff. Not a total gardening newbie but out of practice and there is some stuff I don't know. So...

--the soil in the raised bed is about 4 inches below the top of the wall. Do we need to add soil to build this up?

--the ground hasn't been worked in a while except for my tomatoes and herbs two years ago; planted nothing at all last summer; do we need to fertilize? If so, what kind would be best? We live in the U.S. in Zone 6.

Thanks! :-)