Key documentation is always original source material. In this case that's Watchtower publications. I write and until recently taught history. Most of what you find online is inadequate or wrong. Distrust everything until you can verify it.
On what basis do you hope to debunk the NWT. I had two years of NT Greek and would find the task of 'debunking' the NWT daunting. You can repeat what others have said, but be aware that a significant part of what you find online is wrong. Mantley tried to rebut the NWT claiming they misrepresented him. In fact, Mantly did not write what he claimed. He revised Dana's Greek Grammar and had nothing to do with the quotation in question. So beware.
One anti NWT tract claimed that the Witness translation was criticized by an expert who died 100 years before the first volume of the NWT was released. Be cautious. Use truly authoritative sources, not mere polemics.
The same is true when dealing with Witness 'predictions.' Many things are misstated even in sources that seem authoritative. In the next volume of our book, Separate Identity, we consider Watch Tower expectations for 1881. After considering the secondary and tertiary sources we've written this paragraph:
"Russell and his fellow
believers’ expectations for the approaching year are almost always misstated.
Brown, Bell, and Carson’s Marketing Apocalypse says: “Jehovah’s
Witnesses ... have rescheduled the end of the world on nine separate occasions,”
and cites the 1881 date.
None of the dates they cite were the focus of end of the world predictions.
That they claimed such indicates a profound misunderstanding of Watch Tower
theology. Neither Watch Tower adherent believers nor descendent groups believe
the world will end. They expected other things for 1881. L. L. Dawson and B. C.
Whitsel claimed that “Jehovah’s Witnesses predicted Christ’s second coming in
They derived this from a misreading of an article by Zygmunt, failing to read
any of the original material. Russell and his associated did not believe Christ
would return in 1881. They believed he was already present. There is little
excuse for errors of this nature. Others with some pretension to academic
credentials have made similar claims. One can safely consign their research to
the trash bin of poorly researched history."
My point is that you will find many claims, most of which will prove false. Verify from the original Witness sources.
Back to translation criticism: Go to standard sources, not anti-witness polemics. Among these are Brown, Driver, Brigs, Lang's Commentary; Various Lexicons, M. R. Vincent's word studies, Vines, A. T. Robertson. Also, some fall into the trap of ignoring Witness explanations for controversial translations. Don't do that. Check out what they said.
Others ignore textual context when making their point. This is always a mistake. For instance, when considering John 1:1 controversialist writers tend to focus on the anarthrous theos, arguing over its significance or lack of significance. This is a valid discussion, but it ignores the state of being verbs: ie Jesus was God; Jesus became flesh. These are as important, maybe more important contextually, as the anarthrous theos. If you wish to argue this point to a valid conclusion you must account for the verb forms.
Am I suggesting you give it all up? No. Neither am I defending Witness theology. But I am advising you to be more than the usual amateur controversialist. There are many junk refutations of the Watchtower. Don't write another one. Do your homework. Don't parrot what others say. Verify, verify, verify.