BiocManager has replaced the old biocLite script for versions R >= 3.5.0. Please use BiocManager::install to install Bioconductor packages.
We strongly recommend that users keep their R versions up-to-date (4.0.2 / 4.0.3).
For legacy reasons, the biocLite.R script is still available but only for older R versions. See this link for details: http://bioconductor.org/install/#Legacy
BiocManager::install("biocLite") would be the command used to install a package biocLite, but there is no biocLite package. biocLite is the name of the installer function a long time ago. All the other lines you ran are correct.