Were you able to find ggplot2 in the Packages pane?
Alternatively, what happens if you run this line of code?:
ggplot2::ggplot(mtcars, ggplot2::aes(wt, mpg)) + ggplot2::geom_point()
To explain:
I’m working from the hypothesis that despite your efforts, the ggplot2 package isn’t actually getting loaded. The most likely reason for that is that the package hasn’t successfully installed. That’s why I wanted to see the console output from running the install.packages line.
If ggplot2 has installed successfully, then running the line above should work even if the package isn’t loaded.
If ggplot2 hasn’t installed successfully, you’re going to have to examine the console output from install.packages() to figure out why. For debugging installation issues, it may be easiest if you can find in-person help — since you’re taking a class, are there TAs or a peer support group you can ask for help?