Change font format for Specific Page

Hi, I am trying to change the Body Text for a specific Page. I'm finding that a spacing of 1.7em works for all pages, except for one.

By guessing and checking similiar questions, I've tried this:

Gone to Page Setting within the Specific Page. Then Advanced, and filled in the following code:

<style> .sqs-block.text-block .body-font p { letter-spacing: 0.1em; } </style>

Which of course has not worked, because I am totally guessing as to how and what elements to refer to.

IS THERE SOMEWHERE THAT HAS A LIST OF ELEMENTS THAT CAN BE ACCESSED, AND HOW TO ACCESS THEM?

I hope someone can help me out! thanks