Retweet a hashtag for an account


How do I impliment a twitter account to retweet any tweet by a subscribed follower using a hash tag or a @something? Im trying to spread the word about hunting for homeless veterans in the usa. when someone subscribes to my twitter account how do they authorize that twitter account I created to retweet their send tweet
Jean Andre Vallery
twitter account @homelesvets
I have the api created but not sure how and what to do at this point