I checked the page but didn’t see the section id or fragment id for the link pointing to.
You need to create the section ID or define the ID for html elements like heading, p tags. See https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a (Linking to an element on the same page section)
“could you also tell me what caused the delay in loading the particle, please?”
You are using multiple scripts from Joomla components, It’s hard to check what’s the problem. Could you please let me know the Uikit atom settings for your site ?