Which treatment works the best and fastest for chronic pain?

It depends: There is no "quick fix". Lifestyle modifications including weight loss are important. You dont say why you have chronic pain but dependingon the cause you may benefit from one of several medications. Physical therapy can help. I would suggest seeing a comprehensive pain management facility near you.

Conservative first: Most often chronic pain has an underlying cause and trigger (not always). The treatment is usually directed in that direction. Trying to reduce the symptoms coming from the offending structure. For true chronic issues, "fix" is rarely possible where "control" of symptoms is a more reachable end point. Therapy, injections, medications, even surgery at times, can all help. Get an evaluation soon.