endless legend collection = ??Credits

What?

70 cv, I think. It depends on the us price, so it may be even more. I can see its european price only. :P Keep in mind that there's a possibility it may get bundled.

CV is calculated in USD, not in points or credits. You will get 119,99$ Real CV unless shobo decides to bundle it which is unlikely because the discount is (barely) under the threshold.

1. Please, read FAQ and Guidelines, you'll find most of the information you need there.
2. What's "Endless Legend witch all DLCs"? Could you give a link to a Steam page? It's a bit hard to understand what are you talking about for now.
3. When you start creating a giveaway and press "Review giveaway", you can see it's CV value on preview; still, it's entirely possible that you'll get only 15% of that amount if the game was bundled (again, read FAQ to understand what I'm talking about).
4. If you still have some questions after reading FAQ and Guidelines, feel free to ask.

Credits? Do you mean points to enter other giveaways? You don't earn them, they regenerate automatically. When you create giveaways, you earn CV which is required to level up.