This a part of your theme for welcome message. You can configure on your theme options, For title, descriptions, button and everything what you need here. just put your text on texarea also you can put your image here.
Welcome to amdhas theme
This part for heading and description your site. you can put HTML code on theme options. Its easy just go to Appearance >> Theme options >> General and put your text on the text area there. This theme support 8 different layout for homepage you can choose what you like on theme options page.