Hello Jason,
Thank you so much for using our theme AcmeBlogPro. Please add the below CSS to make the font size little bit larger.
html body{
font-size:18px;
}You can write the other property below the font-size property, but in case of font family, you have a options inside Appearance > Customize > layout/design options > font family to change the font family of every section.
Hope, this will solve your problem.
Regards,
Thanks