How to add custom javascript on the page?

The community member is trying to add a particle effect to a section of their website by using an Embed HTML component, but the effect only appears briefly and then vanishes. They are unsure why this is happening and ask if there is a way to add JavaScript to the entire page instead of using the Embed HTML component.

In the comments, another community member suggests that the "client only" flag is likely missing, which is a setting in the Embed HTML component. Another community member provides a link to a published website where the issue can be seen, and the original poster confirms that the particle effect is visible briefly but then disappears.

The community members discuss the issue, and one suggests that the "client only" flag is the setting that needs to be added, but the original poster is unsure how to do this.