We have checked your website. In the Front Page, you can see the slider layout in the theme.
The sub-header area only display for page title and post title in theme. We think that, you does not require to display header on front page. Because our theme already show slider.
At this time, you used small size images in the slider. Kindly add big size images in this section with resolution 1600 x 550 or 1600 x 6oo. Then your site will look nice.
Also, you can send us your website login details our email id at britetechs[at]gmail.com then we can resolve you small issue in the site. Your login details will be secured.