Is it safe for a novice (me) to replace my oxidized headlights

you can do it its not to difficult only takes a few tools if you j8st pay attention and take your time you can do it no problem doesnt mater as long as you try not to break anything just give yourself a little time and youl learn a few things about how things work it will be fine and ita acually a good way to get acquainted with cars and how theyre put together you might suprize yourself i say go for it
Good luck hope this helps .

Hmm, it does say you need to remove the bumper? Anyway here is how to remove the headlight lens and bumper if needed. Check out the images (below). Let us know if you need anything else.