What do I do if there's no output on the serial moniter?

Welcome to the forum

Please do not post pictures of code or Serial monitor output

You have not even posted your whole sketch

Please follow the advice given in the link below when posting code, in particular the section entitled 'Posting code and common code problems'

Use code tags (the < CODE/ > icon above the compose window) to make it easier to read and copy for examination

https://forum.arduino.cc/t/how-to-get-the-best-out-of-this-forum