Thanks for your question! Unfortunately there is no existing word for "page" so we'll have to paraphrase a bit. "it's" in your writing should be "its", which would translate to the word niil, so if there was a word for "page" you would say "niil pages" for "its pages". "It's" is a contraction that means "it is", which would translate to "nii los".

Here's my personal translation of your line, and I'll explain how I got to it:

Leinu los teyu, ahrk fah pruzah uv nid, mu pah los pel nii.

The literal translation of this is "Our world is our tale, and for good or no, we all are writing it."

"Leinu" and "teyu" make use of possessive suffixes (see page 14 of this guide) to make "our world" and "our tale". I use "los pel" to make "are writing", which also helps a bit with the flow of the sentence ("Mu pah pel nii" vs. "Mu pah los pel nii", a little more rhythm and ease of pronunciation).

My word choice comes down mostly to canon words over non-canon words - the entire translation is canon, which is always a huge plus. Expressing "better or worse" in canon was tricky but if you're fine with non-canon then "pruz uv volz" works just as well.