hi, I bought the theme jhilmil but I can not install on wordpress, he says missing the style.css stylesheet

Hi! I have some questions. Just bought it but I think you should know the places where to change colors etc. If you help with this, then my site is 99% ready after that yoohoo! 1. The color for buttons, active links are in light brown/beige. I want to change it, where can I find it in code? 2. I want to change header picture, as in the title of my site needs to be my sites logo but cannot find it. Also in the footer, would like to add my brands logo not just regular text option. 3. Cant find the [ourbrands] thingie, it shows in every page but I cannot delete it 4. Where can I adjust or delete pages pictures and navigations, change the pics like on SHOP etc.Cannot even in the homepage change it into one big photo without the HOMEPAGE/HOME. Would want to delete this option and leave it blank. 5. In some weird reason, my shopping page is 80% full, it means only 3 rows and its blank space after that, looking my site weird. 6. Cant find where can I edit the welcome message..