Chinese is not a phonetic language. The pronunciation is not related to the writing of Chinese words (characters). A special tool called Pinyin (pronouncing the sound) is created for people to learn Mandarin pronunciation. Pinyin is a way to transcribe Chinese characters so people can pronounce it. The writing of Pinyin is similar to English alphabet.

If you listen carefully, you will find Chinese is a very beautiful language as it has more musical sounds (vowels) than noise (consonants). Except for nasal sound like "n" and "m", all Chinese syllables ends with vowels. So we call them "Final Sounds". The consonants at the beginning of a syllable are called "Initial Sounds".

Chinese is a tonal language. Tones are the changes of the pitch in pronunciation of a syllable. There are 4 tones in Mandarin Chinese. Each Chinese word (character) carries a tone. Different tones carry different meanings. 

Most of Mandarin sounds are easy for English speaker to pronounce some sounds are difficult and requires more practice.