Help with Fixed Background with Content scrolling indefinitely

Site URL: https://www.jorigoh.com/para

Hello,

My site password is 123

 https://www.arcticmonkeys.com/ I am trying to achieve this fix background image while content scrolls pass to the top. I achieve it slightly with parallex BUT it only applies to 1st section, subsquently sections are opaque.

Do i need add multiple of the same image to achieve this? wouldnt that mess up the alignment when it scrolls to the next section's image? Or make subsquent sections transparent?  Or do i need to add a css to drag the section length?

Thanks!