[Theme Horse Support Team]

Hi Chaimongkol,

You can change the Navigation font family via Go to Appearance -> Theme Options -> Typography Options -> Font Family there you will see the Navigation option to change the font-family. Choose the font family that you like and click on save button.

And for the sidebar first Go to Appearance -> Theme Options/Customize -> Webmaster Tools -> Analytics
and paste your font script in the header script box which is given by font integrate service such as Google Web Fonts
Now integrate the font into your CSS Go to Appearance -> Customize/Theme Options -> Design Options Tab -> Custom CSS paste the following CSS code and Click on save button:

#secondary {
    font-family: YOUR-FONT-FAMILY;
}

Replace above text YOUR-FONT-FAMILY with the one you want to set in the sidebar.

Thank you!