It provides us opportunity to learn different people, which add(还是adds）more fun and color into my life.
非限制性定语从句，我想表达的意思是“这一点”增加了更多的乐趣。
我觉得应该用adds，但word纠错改成了add，这是为什么呢？
which指代前面整个句子，这是非限制性定语从句和限制性定语从句的区别，此外，你的句子还有些错误要注意：it provides us with an opportunity to get to know different people, which adds more fun and color to my life....
