Step 1: Decide what range of motor speeds, loads & accelerations you wish to control. Also decide whether you wish to change the motor direction.
Step 2: Find a qualified electrical/electronic engineer who can do this wthout killing themselves or anyone else.
I'm sorry to be so harsh, but the question reveals such a lack of knowledge and unwillingness to google that any advice suggesting you can do this yourself could result in a hazard to you and all those around you.
Now, google around a bit and get some idea of the hazards associated with mains electrical power, switching, protection, immobilisation and signal isolation. Then come back when you have a specific question.
