Not many characters hold exactly the same meaning - however they have the same English definition. For example 明 and 亮  are both talking about different types of bright. You cannot use them interchangeably. 

It seems hard - but just start :) .... After a while, you will just suddenly know the meaning of so many characters!

Like see and watch in English, these words have their own usage.

Just keep learning and practicing, and it will come naturally.

Hope my answer could help. Btw, I'm learning Spanish, add me on Skype if you are interested. 

我觉得你买一本字典比较好，新华字典或者是辞海，遇到不懂的可以翻阅，学习中文也会简单很多。如果你需要剩下的解答可以告诉我，我会教你，当然line上交流也可以。

 I think you buy a dictionary is better, the Modern Chinese Dictionary or Ci Hai, encountered do not understand can read, learning Chinese will be much simpler. If you need the answer to tell me, I will teach you, of course, line can also be on the exchange.

line（app）