What CMS would be best for the following sites?

Hi guys, I have experience with C# and Java, but none with web development and CMSs for now, I have enough time to learn what is needed however. I would like to inquire your opinion on what free CMS would be best to use for the following 2 sites, separately of course. My only requirement for the CMSs is that there are good video tutorials for them, as I find this to be fastest way for me to learn something new.

1.An online library where anyone can publish his works - books, stories, comics or any other form of written content. They will be free to download, but authors can receive donations for them, from which the site will take a small commission. So basically something like a book store but with no shopping cart, with donations, users can upload books and receive money. Users can also invite others to publish their works and receive 1% of their donation - something like a very basic referral system.
This one will probably require a lot of custom work too, but still which CMS would give me the best start to work with?

2.A combined news and deck sharing site for a digital trading card game. Something like Heartpwn, but simpler.

 

Narrowed it down to 3 - Umbraco, Orchard or Nopcommerce would be best in your opinion?

 

Why don't you consider something like WordPress? It has by far more community support and good tutorials (including video tutorials that you have mentioned before). I think for the site #1 as you have describet it, WP would be the perfect option. It is pretty simple to create custom content types and custom fields. As for the site number 2, I think Umbraco is a good choice.
P.S. I'd recommend to read these articles kind of see why I recommend WP for the first site. #1 - on WP support (https://www.cms2cms.com/blog/how-to-get-help-with-wordpress-dos-donts/) #2 - WP tricks and hacks (https://www.cms2cms.com/blog/most-wanted-wordpress-tricks-and-hacks/)