Troubleshooting for R, RStudio, and Tidyverse installation

Why doesn’t my R look like your R [software]? RStudio says that it cannot find the R binaries. We cannot install software (on iPad, Chromebook, etc.) tidyverse cannot be found [package] is not available for R version … there is no package ‘rlang’ there is no package ‘broom’ rlang and/or broom still do not work How do we know which is the RMD file and which is the HTML file?