I want to write a guide for the game "Steven Universe: Attack the Light", but how can I write the guide?

Where is this option?

Go to the "guides" page on the menu of the game, then click on the three-dots icon in the top-right side --> Add guide.

Thank you.

By the way. I saw that some guides have images and videos. How do they get into the text?

You should paste the link to a picture or video, and they will be automatically embedded in the text. Here are the formatting guidelines: https://www.speedrun.com/the_site/thread/wrefn

Thank you,buddy