Not able to install PMCMR package in R studio

To update on the installation.
On the terminal :
I got the homebrew installed on my personal MAC ( even though it says you don't need to be sudo to install homebrew, i realized you need to, or maybe it was my company's setting on work laptop! I tried installing homebrew in local but did not work. so I switched to my personal mac.)
then did the brew install mpfr. This automatically also installed gmp. So there was no need to do brew install gmp.
In R studio:

  1. I did install.packages("PMCMRplus") and everything got installed fine !
  2. library("PMCMRplus")
    Warning message:
    package ‘PMCMRplus’ was built under R version 3.6.2
    even though I got a warning it loaded !
    Thankyou andresrcs for all your help!