Some students use studying vocabulary for the GRE as procrastination to avoid studying for the more challenging material, but there is value in spending some time studying vocab.
Vince Kotchian does a good job covering studying GRE vocab in his brief ebook, so I recommend checking it out. The gist is that studying for vocab should be focused in chunks of words with spaced repetition and review.
Choosing the list to study from can also be daunting. The best (reasonably) short list comes from Prep Scholar. They have a list of 357 words that I often recommend. There are four good ways to get this list. Prep Scholar’s website has a pdf of the list, printable flashcards, a quizlet deck, and an Anki deck. The Anki deck can be hard to find, but any of these methods will work well.