Hello @Rangod,
Please find below the instructions regarding each of your issues listed down :
1) The Business park Pro theme already has an option in the customizer that lets you choose the icons with fa-icon class and the color for the icon background in Admin Dashboard > Appearance > Customize > Sections > Service. Please refer the gif below for usage instruction in the section :
2) The photos in the Team Sections comes from the featured image you have set for individual team member. For the image to show up edit the post with the id you have chosen and set the featured image for the post. The featured image will then be shown in the team section.
3) The photos in the Blog section also comes from the featured image you have set for individual posts. For the image to show up edit the post with the id you have chosen and set the featured image for the post. The featured image will then be shown in the team section.
4) The icons can be managed by entering the Font Awesome Class of your desired icons. for reference of the font awesome icon classes please see the link here : http://fontawesome.io/icons/
Please write back to us if you have any further confusions / queries.
Hope this Helps,
Best Regards !!