Multiple boxes with Read more / Read less function - HELP

[Floisok]

Hello,
My Goal:

I want multiple boxes with Read more / Read less function. I am able to create one working box but when adding more it doesn’t work. I am not the experienced.

What i have:
https://codepen.io/flo44781/pen/agZWwo -> One working Box with Read more / Read less

When i add new boxes do i need to to re write the Java Script for every new box i do?

Best regards,
Florian

[Floisok]

Can i say the script that it only affect box-1 another script should only affect box-2 …