What’s the ch sound? My intuition from German class is that ch represents a throaty hhhh. Somehow that got spoiled into k in most English words.
Every c in Pacific Ocean is pronounced differently. C is a silly letter.
If you mean the standard German from Germany, there a two variants. At the end of a syllable it is like you described (kind of throaty hhhh). For the beginning of syllables think of sh and open your mouth.
It varies between dialects. Swiss German speakers tend to stick out to Germans because we pronounce the ch in a much scratchier way than is accepted in Standard German.