Is it importante to learn chines ñame

rogerloh

hi, i am a new student - cantonese speaking. i would like to know how should we pronounce ;-    Chize (He -Sea Point,LU 5)
He -    is it as in English, (He is a man) or in LI 4 Hegu  ( this is pronounced as Her Goo- as in Igloo) although this is in Mandarin as all the names in pinyin form.
What about the word Sea - is it as in English?-(The sea is very large and deep)
can someone Please clarify for a more accurate pronunciation.?
thanks.