The problem he tries to avoid me with no reason and blocked me & keep me away !! i know he is not on his mind with cocaine!! How can i help him

First things first.
He wont be able to go straight cold turkey, so get that out of your mind for a month or 2 atleast. If you make him go cold turkey straight away the problem is that he's pscychologically addicted to the snow so his mind will explode when he's not beeing fed it. What I suggest you do is instead start by trying to give him a less harmful drug which has similar effects, what this will do is it will give him the high he wants without making him go nuts over it. After a while move him down to just weed only. Weed is easier to stop than Cocaine,
When he transits from coke to weed only it will be easier for you to comtrol/ start building him back again.
Honestly it wont change in a momth it could take up to 6 months but if he means a lot to you or if you mean a lot to him then the least I can suggest is stand by him untill you know you cant anymore.
If this does not work I suggest you go to a Therapist who will most likely try talking him out of it. Rehab is always a last option and i suggest you avoid that unless the situation is literally at the end.
+1 answer in: “If u have a friend he/she becomes addict to Drugs,weed etc !! Will u tell his/her Family ? Or leave her/him ??”