Couldn't decide but round about three, somehow, did (8)
I believe the answer is:
dithered
'couldn't decide but round' is the definition.
I can't tell whether this defines the answer.
'about three somehow did' is the wordplay.
'about' indicates putting letters inside.
'somehow' indicates anagramming the letters.
'three' is an anagram of 'there'.
'there' placed inside 'did' is 'DITHERED'.
Can you help me to learn more?
(Other definitions for dithered that I've seen before include "Vacillated, was indecisive" , "Was undecided" , "Hesitated" , "Vacillated, wavered" , "was vacillating?" .)