Regularly find kid on Twitch silly (7)
I believe the answer is:
idiotic
'silly' is the definition.
(I've seen this before)
'regularly find kid on twitch' is the wordplay.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'twitch' becomes 'tic' (tic is a kind of twitch).
'find'+'kid'+'on'='findkidon'
The alternating letters of 'findkidon' are 'idio'.
'idio'+'tic'='IDIOTIC'
(Other definitions for idiotic that I've seen before include "Half witted" , "Senseless" , "without intelligence" , "Absurd, crackbrained" , "Fatuous" .)