How to get a CSV file from a T-SQL in SQL Agent

I am using SQL agent to schedule a task. This task is the execution of a script that performs a query to several databases and concatenates the output. I have managed to obtain a file but not a CSV file, that is, I cannot obtain a file separating the fields by commas or periods, it is rather a txt file with columns. How can I achieve this? In the options configuration I do not see the option to define these output parameters in the files that result from a T-SQL