First daring four in, started going deep into the water (6)
I believe the answer is:
diving
'deep into the water' is the definition.
I can't tell whether this defines the answer.
'first daring four in started going' is the wordplay.
'first daring' becomes 'd' (1st letter of 'daring').
'four' becomes 'IV' (Roman numerals for four).
'started' suggests taking the first letters.
The initial letter of 'going' is 'g'.
'd'+'iv'+'in'+'g'='DIVING'
Can you help me to learn more?
(Other definitions for diving that I've seen before include "Throwing oneself into water" , "Water sport" , "Plunging into water - falling in the air" , "Plunging oneself into water" , "Plunging headlong" .)