Supervisor doesn't give me a chance to contribute more and gives himself first authorship, how to approach this? My supervisor proposed a test, just a concept and I designed the experiment and executed the lab work all by myself. 

After the experiment was done and I presented the data (in nice figures and tables) to my supervisor, this supervisor asked me to only write down how I did the experiment but not anything related to the other parts of a manuscript. Yes, it's clear that my supervisor told me not to touch the results and discussion, etc. I thought this might be the way my supervisor does things, I mean this professor might want to do things step by step, so I didn't comment on this. 

Two days later my supervisor showed me a whole manuscript, a manuscript almost ready for submission, this professor wrote the whole manuscript without any discussion with me! 

The professor told me that he/she would like to be the first author because I don't have intellectual input into the manuscript... I think this is ridiculous, isn't the experimental design a kind of intellectual contribution? And I have this question to my supervisor in my mind... how can I add my thinking into a scientific publication if you don't even allow me to participate in writing the manuscript? I'm not sure whether I did the right thing but I didn't really make a comment on his remarks. I was shocked when I was in this professor's office.

What is the best way of approaching this problem?

We only have a few students in this lab now, we are new so I cannot guarantee nothing like this happened in the past though. Any suggestions?
Well, so let me phrase it this way: Your professor had the original idea (which you then fleshed out and executed) and then did the most difficult parts of the writing. I typically see that what students struggle most with are introductions, providing context, the literature review, and forming conclusions. If that is true for you as well, then the parts your professor wrote would have likely taken you a long time to do. If you see it this way, then it is, at least, not inappropriate that your professor would be the first author.

What I think most people would probably agree with you is that doing all of the writing him/herself is a poor way of teaching you how to do it. Ultimately, we educate students because we want them to become knowledgeable and independent, and that can only happen if we teach them how to do it, not do it ourselves. If your professor is still young, you might want to simply ask to be included in the writing part in the future, and say that you'd like that to happen because you'd like to learn how to do it.