Liquid uses two distinct font families for display and body fonts: Lato is used as the body font as well as the h* and xh* display font, while the MFont is used as the b* and xb* display font.
Font loading is taken care of by Liquid's global CSS, so there's no work to do on your side, except for loading the required CSS file. Please refer to our documentation on importing stylesheets from Liquid.
For more information on display fonts, take a look at the documentation for the ld-typo component.
Please also have a look at the documentation on Typography for general usage recommendations.