See here how to add custom fonts to your website.

If you'd like to use your own font styles go to Configuration → picturemaxx → Font selection and configuration. 

• To upload your fonts go to Custom Fonts and click Add Custom Font.

• Choose the Font File to upload. The font file must be in WOFF format since that is accepted by all modern browsers.

For a more detailed explanation with a screenshot and definition of each field, go to Change Look & Feel.