What's origin of the Chinese word for "time" (时间)?
The '日' radical of '時' indicates it is related to 'sun; day'
The '寺' /si4/ part in '時'/shi2/ is the phonics component
(寺 means 'temple'.  As the phonics component of 時, the 'temple' meaning is irrelevant)

時 means 'time; hour'
四時也; 本春秋冬夏之稱。引伸之爲凡嵗月日刻之用
Originally meant four seasons (四時), extended to mean 'years, months, days and hours' (time)

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間 means 'space between; interval'

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時間 means 'time' (intervals of days, hours)

There are other time related words in Chinese:

光= light; 陰= shade
光陰= light and shade= day and night= time (cycle of days and nights)

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寒= cold; 暑= hot
寒暑= cold and hot= winter and summer= time (cycle of seasons)

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歲= year; 月= month
歲月= year and month= time (passing of years and months)

Jeremy wrote:

if there is a place where it is possible to know the origin of Chinese characters please share

You can find the origins of many Chinese characters in 說文解字 or just wiki it