To assign a level in a sport to a customer, we must first access the client list at:
Customers -> Customers.
Once inside, we will press the icon 
of the client to which we want to assign level in some sport:
We will go to the Game information section:
In the tab "Level of play" we select the sport in which we want to assign the level and position.
From here we will indicate the current level of the client, in addition to the position in which he plays (to Paddle in this case). You can also indicate if the customer is federated, its category and its license.
Once we have finished the process click Update.