My site is penalized on google board core algorithm. So i request you how to recover this.
If you have received a penalty notice from Google, does it not explain why your site was penalised and tell you what steps to take?
Assuming what you meant to ask about was a “Broad Core” algorithm upadte, the quick answer is: there is nothing you can do.
From what I have read after a quick search on the subject, core updates happen very frequently, often twice a day. The “Broad” core update is said to not penalise poor quality sites, but is intended to improve the relevancy of a user’s serch results.
Of course this may result in a certain page dropping in ranking for a particular search term, but it is not that page being penalised, but more a case of a more relavant page being promoted in ranking.