Install the font first before use.
How to install font
windows :
https://www.fontspring.com/support/installing/how-do-i-install-fonts-on-my-windows-pc
mac :
https://www.fontspring.com/support/installing/how-do-i-install-fonts-on-my-mac
FOR FULL GLYPS AND COMMERCIAL PURPOSE:
http://saridezra.com/product/katherine-script-premade-logo/
You can also buy it on Creative Market:
https://crmrkt.com/pvwr14