Hey here’s some answers for your questions.
To cover the whole background what you need to do is go to the page builder where you have all the rows for your front page. Click on the little wrench icon for the row containing the services widget and click edit row. You’ll get a pop up and in there on the right will be a couple sections. Click on layout then scroll down to row layout it’ll likely say standard. Change that to full width. Ta-da your background is now full width. If you want to change the color or make the background an image simply close the layout tab and click on theme. There you can set a background color for the row or put a URL for an image. Note: I’d recommend hosting the image on your own web hosts servers, because if you use a link from a different site and they go down for maintenance or something then your image won’t show up.
As for the icons you have to say which icon you want for each item. When you set up your services (after clicking the services tab in the WordPress menu thing on the left of your screen) there will be an option towards the bottom for the service icon. There’s nothing in that page that indicates what icons you can use that I’ve seen, but after a little research I got this.
Those are the icons they use for this theme. You have to input the code for the icon you want i.e. fa-calendar for the calendar icon.
As for employee photos you have to first click on the employees tab in the left menu thing to set up employees. Click add new and when you scroll down you’ll see where to upload a pic for the employee.
Hopefully you’re able to follow all of that good luck with your site.