Need help with github repo organazing

Hello. I am new in GitHub and Yii2. I’ve created a shop application based on Advanced Template - https://github.com/CyanoFresh/yii2shop . So I want to create another application that extends this Yii2Shop. I uploaded it on my new application by zip. So I want to develope yii2shop and I want to have changes from yii2shop in my new project. Ho I can do this? Please explain