musicianprofile
Hi
The font size of Heading will be from the template you are using example : http://prntscr.com/ufbhga
You can apply custom css for this
.ada-packages-title h2 {font-size:12px;}
.ada-packages-subtitle h4{font-size:10px;}
This way you can customize it.
For the other text is from /com_adagency/includes/css/ad-agency.css
You change it from file but i suggest you to override it via custom css in your template
http://prntscr.com/ufbia7
Hope it helps.