汗 is built from the 氵 (water (left)) and 干 components.
It reads カン like 干, as do 幹, 岸, 刊, and 肝 — learn 干 once and the family's reading comes with it.
A common word using 汗 is 汗 (あせ), meaning “sweat, perspiration”.
Kanji that look similar include 汚, 江, 池, and 汁.
