Came up against a bill and what goes on it (6)
I believe the answer is:
accost
'came up against a' is the definition.
I can't tell whether this defines the answer.
'bill and what goes on it' is the wordplay.
'bill' becomes 'acc'.
'and' is a charade indicator (letters next to each other).
'what' becomes 'os' (I am not sure about this - if you are sure you should believe this answer much more).
'goes on' is a charade indicator (letters next to each other).
'it' becomes ''t' (abbreviation. e.g. in 'tis).
'acc'+'os'+'t'='ACCOST'
Can you help me to learn more?
(Other definitions for accost that I've seen before include "Approach boldly or aggressively" , "Approach or confront boldly" , "Approach boldly or impudently" , "Approach and address (someone) aggressively" , "Challenge" .)