What dental treatment should I go through? I have braces and broken frontal tooth and many cavities. (photo)

I would first go get a thorough evaluation with an orthodontist to plan out the course of treatment. I see that you have active appliances in and from what I can see you also have active cavities. You will definitely want to get those cavities filled before moving on with any further orthodontic treatment. An orthodontist will be able to direct the course of treatment and what final restorations may be needed after the teeth are moved into their proper position. Typically, all disease is taken care of first, such as cavities and then orthodontics is done. After treatment any crowns, implants or bridges are placed as needed by the restorative dentist.