http://www2.stat.duke.edu/~tjl13/s101/slides/unit6lec3H.pdf

thanks

Dear Yassine,

I hope you will get some help form the following link:

https://www.r-tutor.com/elementary-statistics/simple-linear-regression/prediction-interval-linear-regression#:~:text=Assume%20that%20the%20error%20term,is%20called%20the%20prediction%20interval.

Best,

Firdos

prediction intervals are only concerned with past and future observations, rather than unobservable population parameters, they are advocated as a better method than confidence intervals by some statisticians,