Small lifestyle changes （主语）can make （谓语动词）a huge difference （宾语）and can reduce （谓语动词）the environmental impact of our daily activities.（宾语） 

and 连接两个并列的“动宾结构”；of our daily activities 是 impact 的定语。

Small lifestyle changes can make a huge difference and can reduce the environmental impact of our daily activities. 

【翻译】生活方式的小小改变可以带来巨大的改变，并且可以减少我们日常活动对环境的影响。