Parallax issues and weird header

Hello,
I am using elementor pro but the support has been so slow.
I have set up some parallax on the site but it’s very buggy on computer. As you can see it’s “laggy” and very slow.
Second problem in the header men, the point with submenus gets weirdly dragged down.

Do you have solutions for those problems?

Thanks!

The page I need help with: [log in to see the link]