Termux ships with a package manager called pkg, and almost everything you add later arrives through it. These questions cover refreshing the index, installing and removing, and the private prefix where all of it lands.
Each one is marked as you go, and the explanation arrives straight after, which is
the part worth reading.
4 questions, marked as you go.
Tasks
These need your own device. Run the command in Termux, then paste what it printed.
The marking looks at what the output means, so spacing, version numbers and
ordering do not matter. If you have not installed anything yet, the
lesson covers the setup.
Show the Termux prefix
This prints the directory Termux installs into, then lists what is inside it. The listing is the standard layout of a Linux install.
Run this in Termux
On your own device. Nothing on this page executes it. The command runs in
your terminal, and this box only reads what you paste back.
echo $PREFIX; ls $PREFIX
The first line is the path itself. The lines after it are the folders inside that path.
the prefix is printed as an absolute path
the prefix holds the standard program directory
both the prefix and its contents are shown
the commands actually ran
What a good answer looks like
Two parts. The first line is an absolute path ending in usr, which is where Termux keeps everything it installs. The lines after it are the folders inside: bin for the programs you run, etc for configuration, lib for shared libraries, and others such as share and var. The exact set of folders differs a little between devices, depending on what is installed, so read the shape rather than expecting a fixed list.
Marking your own work
Both halves of this are checked in your browser, with no server involved, so nothing
stops you from pasting output you did not run. The tasks are written so that the
easiest way to pass one is to actually do it and read the result, which is the whole
intention.