You can set default style options for headings and text in the theme, then override them if you need to in the Beaver Builder plugin editor.
Heading options are set in Customize > General > Headings. Text (other than headings) options are set in Customize > General > Text. You can set the following options separately for headings and text:
- Font family, size, weight, format
- Line height
- Letter spacing (headings only)
See the article about the General tab's Heading and Text settings for more information.