Advice for Contemporary music

Can you give me some advice at writing contemporary music... i can't image what contemporary music is ? Pls give me some example and advice// Thank you so much

That's a little bit too broad a question. Do you know what you're looking for? What period? What kinds of sounds?

Here are some links that will help you:

1) https://en.wikipedia.org/wiki/Contemporary_classical_music

2)  a) https://www.theguardian.com/music/musicblog/2012/apr/23/welcome-new-contemporary-music-guide

b) https://www.theguardian.com/music/series/a-guide-to-contemporary-classical-music

3) https://www.amazon.co.uk/Composing-Contemporary-Music-Students-Guide/dp/1845214072

4) https://www.berklee.edu/berklee-today/summer-2010/contemporary-music

However, my personal opinion is that you don't just deliberately choose to compose in a "contemporary" style. You just follow your compositional inspirations and go where they lead you. But of course, it will help to be familiar with the different styles and what they entail.

In my opinion (I love writing contemporary music) you need first a strong base on tonal and classical harmony. Also, it's good to know how to work with motive manipulation.

Then you have to study the several languages:

1. Triadic extended harmony: chords with ninths, elevenths, thirteenths

2. Impressionism. Parallelism, chord planning, non-functional triadic harmony

3. Harmony by 4ths/5ths, by 2nds/7ths and clusters, combination

4. Non-serial atonality and pitch class sets

5. Serial tonality and dodecaphonism

6. Alternative scales, modes.

7. Messiaen. modes of limited transposition, new chords,

9. Bartók: extended chromatic functional axis system

10. Polyrhythm, polymeter, polytempo

11. Extended techniques in instruments.

12. New Forms.

and etc, etc, etc....

The book by Vincent Persichetti is a good start point.

Thank you for given my some advice.. 
Can i ask.. Is this contemporary music or not ? or pop music ? 

22 minutes ago, Hidetoshi Guen said:

[...]

It's contemporary in that you wrote it in a modern time, but, no, it doesn't really follow the conventions on the 20th or 21st century harmonic techniques.

That's totally tonal and functional.

You have thousands of examples of contemporary (academic) music on youtube. With scores. Take a look.