Changing forehand backhand

Hi, I´m with a lot of difficulties with to change quikly the backhand for the forehand.

Can you tell me how to do ?

Hi,

To be able to change quickly first think about your focus and how well you are watching the ball.  For our Premium members we also have a tutorial on Anticipation which will help.

Then think about making sure you are in a central position and square to the table so that you don't need to change your leg position too much between the two sides.