How do I put an article in a block?
I don't know if there is any shortcut to put the article into Block, but usually I use Views for that. After installing Views Module 


create new Views and select content of type Article
Check on Create a Block and Continue and Edit 
In Fields, Select the fields you want to display eg: Article Title, Description, etc.
Use the Filter to filter results.


If you want to display only the latest Article, then use Sort by Post Date Desc and in Pager settings display max items to 1 with No Pagination option.

Go to Structure->Blocks and select your theme and you can enable/disable what blocks you want to display and where. If you are unsure about the regions in theme then click Demonstrate Block Regions

This looks one heck of a task, but playing around Views would make you more comfortable with Drupal.