Splitting Long Texts and Handling Empty Columns in AI Generated Sentences

I have two problems. Many of my bodytexts are too long. Can you split the text if it exceeds a certain lenght? Second question: I have given AI two columns to use for personalized sentence. It says "Missing output" if one of them are empty. I have tried to comand it to use only one of them if the other is empty. Can anyone help? 🙂