How to be ready for manufacturing?

You should definitely start talking to some manufacturers before you worry about the format.

MS Word is NOT going to cut it, though, I can tell you that right now. You'll need Photoshop almost certainly (or else Illustrator). As ElKobold said, they'll need a 300dpi CMYK PDF of the card with appropriate safe zones and bleeds, and I have no reason to believe that Word is capable of doing any of that. And yeah, surprisingly my manufacturer wanted the cards as individual files, though I only had like 17 of them.

If your cards are 8.5 x 14cm, then you DEFINITELY need to talk to a manufacturer, because they might not be able to do that. Cards require a particular size of die to punch them out, and you don't want to be doing this custom. A tarot card is reasonably standard and is 7 x 12 cm.

You should definitely find an artist for your box. That will require photoshop or illustrator for certain, because it's not just a single image, it's two big foldout things that need the right bleeds, etc. I own Photoshop and provided all the other PDFs, but I STILL had my artist do the box for me.

A cardboard storage thing with no printing is probably something the manufacturer will figure out for you. Just tell them what it should look like. Same if it's a vacuum-formed plastic insert.. They should know how to get cards into a box securely.

You'll need a UPC code to sell anywhere other than your own site. You can get one cheap. Check ezupc.com, which is what I used.

Rules will also need to be a PDF. Now, MS Word can do a PDF output I think, or you can get a free app thingy that looks like a printer so you "print to PDF". Won't look super professional, probably, but maybe you're a Word expert. And I can't guarantee MS Word will be friendly for things like bleed area.

2000-5000 is a hell of a lot of copies. I mean, this is going to cost 5 figures for sure. Actual MOQ will be 1000 units.. There's probably a price break at 2500 for most manufacturers.

Your life will be easier if you have an artist you can task with getting all the proper formats for you.. someone who owns the Adobe suite. Even if you're not hiring them to do art. Probably a "print graphic designer"? Something like that.

Send me a PM if you'd like the contact info for my manufacturing rep. We never had any real communication problems by email, and she can get you a quote. Chinese New Year stuff should be just winding down. I'm happy with the quality of all my components.

I can also probably send you some examples of print-ready files I sent to them.

You can see my completed game at https://boardgamegeek.com/image/4530889/heroes-treasure . The cards there are tarot size.

As Jay103 mentioned 5000 copies are a lot.
To sell them, it helps if your game and the cards are looking good. So you probably want to hire the artist also for your cards.
For your first project I highly recommend an artist with experience in board games.

Then ask your manufacturer for a rulebook, the cards, an inlay and the box.
Also ask them for the regular size of a printed sheet of cards. Some manufacturers have 11 x 9 = 99, so 100 cards can be much more expensive than 100.
Also ask them for calculations of different prin run size, e.g. 2000 copies, 3000 copies, and 5000 copies.