I hope the Title with the Picture say it all what I am looking for to do. 
Calculate the amount of characters, then split at the next period and split the text in both text boxes. You can even add a hook beforeInsert and split it in to two fields so you just need to connect both text boxes to your database.
Hi Carlos thank you for your advices, but I do not really understand your approach.
How should I calculate the characters? What you mean with “split at the next period”? And I do not know what a “Hook”. 