I feel like I'm going in circles here. I have R 3.6.0 installed, and it clearly shows this is the version I'm using when I enter the interpreter:

$ R

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Platform: x86_64-pc-linux-gnu (64-bit)

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>

Next, I follow the instructions on the Bioconductor website for installing BiocManager:

> install.packages("BiocManager")
Installing package into ‘/share/apps/rmodules’
(as ‘lib’ is unspecified)
Warning in install.packages("BiocManager") :
  'lib = "/share/apps/rmodules"' is not writable
Would you like to use a personal library instead? (yes/No/cancel) yes
Would you like to create a personal library
‘~/R/x86_64-pc-linux-gnu-library/3.6’
to install packages into? (yes/No/cancel) yes
trying URL 'https://cloud.r-project.org/src/contrib/BiocManager_1.30.4.tar.gz'
Content type 'application/x-gzip' length 242304 bytes (236 KB)
==================================================
downloaded 236 KB

* installing *source* package ‘BiocManager’ ...
** package ‘BiocManager’ successfully unpacked and MD5 sums checked
** using staged installation
** R
** inst
** byte-compile and prepare package for lazy loading
** help
*** installing help indices
** building package indices
** installing vignettes
** testing if installed package can be loaded from temporary location
** testing if installed package can be loaded from final location
** testing if installed package keeps a record of temporary installation path
* DONE (BiocManager)

The downloaded source packages are in
    ‘/tmp/RtmpFDxU5w/downloaded_packages’

But then when I try install a package from Bioconductor, it says I'm on an old version and sends me to the exact same website I used to install it in the first place:

> BiocManager::install("normr")
Error: Bioconductor version '3.8' requires R version '3.5'; see
  https://bioconductor.org/install

How can I get it so it's using version 3.9? I'm on a computing cluster which is why I have to install to a personal library. Is that causing this issue?

Is there a package 'BiocVersion' already installed, perhaps in /share/apps/rmodules? Use "BiocVersion" %in% rownames(installed.packages()) If so, remove.packages("BiocVersion"), but probably this indicates that you're trying to re-use the R-3.5 library with R-3.6, which is generally not a good idea. You might instead investigate how to set .libPaths() (see ?.Rprofile) so that it does not include that path.