As one person without large resources the highest impact thing you could do today for the type of area you are describing is to procure a firearm and start killing drug dealers.
I'm not suggesting you do this but this is without a doubt the answer to your question.
This is nonsense. Even if I take your comment in the non-literal sense "get rid of drug dealers" then decriminalization has shown to be much more effective.
I'm not suggesting you do this but this is without a doubt the answer to your question.