How to change font family of entire template and joomla

How to change font family of entire template and joomla,I am using Ja Argo template and Joomla 3.10.

JA Argo is based on T3 framework, you can check out this guide for how to work with fonts: http://www.t3-framework.org/documentation/bs3-customization#add-fonts

This is one of premium template and it requires active membership to get support & updates, pls renew your membership first.

Regards

Thanks Saguaros!