Hello,
You can change the font by means of Advanced typography option, which allows to choose the item from a drop-down or insert your custom CSS class in the custom selecror. Please navigate to the Theme Settings > Typography > Advanced Typography.
Here is the documentation providing more detailed instructions: https://xtemos.com/docs/woodmart/advanced-typography-settings/
As for the breadcrumbs, deactivate all the plugins not related to the theme and check the issue, if the problem remains, leave the plugins not activated and provide the site admin access to the private area
Best Regards