ElegantTheme: Evolution easy customization

Hello, my blog site is http://www.blogdenuria.com

I’m using ElegantTheme called Evolution.

I selected the BlogStyle option, how ever I want to do some modifications on what I’m currently getting.

1) I want to have a larger thumbnail maybe 400×400 just below each post title, and then an scrept of 200 words.. and a read more button.

2) Also I want to add a Leave a comment button (that opens the post in the same window and takes you to the comment box)

3) I want to remove the left column next to my posts with post information (author, number of comments, date, etc… and put it in a single line, just below the post title.

If anyone can give me any light on how to accomplish this, I would be forever thankful.

Thank you in advance