Automating the Google sheets prep process for a newspaper report

The job is taking data sheets with mostly text data from local authorities and spitting out reports to be published. Using an addon in Google sheets lets me take the rows and columns and spit them into a document with the sentence structure needed to be published.

Am hoping to automate some of the cleaning and processing of the sheets with Python. For example, the time column is formatted in military time and needs to be converted to the 12hr standard time by inserting a new column and using left, right and text functions.

Also a lot of grammatical fixes, spelling out abbreviated words etc to be done before it can processed by the addon and sent to a document.

Does anyone know where to start for trying to learn how to use Python to handle these repetitive formatting/cleaning tasks? It seems like programming the computer to do a lot of these processes automatically is possible, just don’t know of any resources to learn this from.