It’s my belief it will be retracted, too (5)
I believe the answer is:
tenet
'it's my belief' is the definition.
I can't tell whether this definition defines the answer.
'it will be retracted too' is the wordplay.
'it' becomes 't' (abbreviation. e.g. in 'tis).
'will' says to put letters next to each other (I've seen this in other clues).
'be retracted' says the letters should be written backwards.
'too' becomes 'tene' (I am not sure about this - if you are sure you should believe this answer much more).
'tene' reversed gives 'enet'.
't'+'enet'='TENET'
Can you help me to learn more?
(Other definitions for tenet that I've seen before include "That's the law" , "Dogma or principle" , "Belief held as true" , "Article of faith; doctrine" , "Adiaphoron" .)