Yeah, I feel the same. It's hard to find relevant information, they are kind of scattered all over the place. I am a newbie too, since last month. Let me know if there are more questions. They will be good for newbies in future.
Not sure about the number, but it's like 5 for each lane so 15-20 in total? All of them require gold now, 4000 gold each. But you get more than that in rewards in return (battle chests, gold, etc)
This is because 5 cards were changed in the recent patch notes. To be fair to those who crafted those cards, they can be redeemed at their full cost so those who have invested in those cards were not disadvantaged. This will revert back to normal after a week or so, I think.
You get a new card every 10 levels. No guarantee of rarity or whether it's new though. I think it's at least rare or better.
This is good for newbies too. But you probably know already.
Good guide for improving your gameplay
Pandora rewards and details
How are points accumulated and what are the rewards for each pandora run?
What reward will pandora points will give you at the end of the season (monthly)
Cappucino's Pandora Tier List, for evaluating values of different cards and treasures during drafting
Crafting Guide for Legendary
Legendary Tier List
Make sure you check out youtube, like:
Faeria official channel,
luuu 90 and
@J0k3se 's youtube
They all have really good guides and tutorials.
And all the pretty artworks in game: cards, orb, avatar, well, etc