How can I find a file/directory that could be anywhere on linux command line?

To get rid of permission errors (and such), you can redirect stderr to nowhere

find / -name "something" 2>/dev/null

"Unfortunately this seems to only check the current directory, not the entire folder". Presumably you mean it doesn't look in subdirectories. To fix this, use find -name "filename"

If the file in question is not in the current working directory, you can search your entire machine via

find / -name "filename"

This also works with stuff like find / -name "*.pdf", etc. Sometimes I like to pipe that into a grep statement as well (since, on my machine at least, it highlights the results), so I end up with something like

find / -name "*star*wars*" | grep star

Doing this or a similar method just helps me instantly find the filename and recognize if it is in fact the file I am looking for.

The find command will take long time, the fastest way to search for file is using locate command, which looks for file names (and path) in a indexed database (updated by command updatedb).

The result will appear immediately with a simple command:

locate {file-name-or-path}

If the command is not found, you need to install mlocate package and run updatedb command first to prepare the search database for the first time.

More detail here: https://medium.com/@thucnc/the-fastest-way-to-find-files-by-filename-mlocate-locate-commands-55bf40b297ab

If need to find nested in some dirs:

find / -type f -wholename "*dirname/filename"

Or connected dirs:

find / -type d -wholename "*foo/bar"