If you have a xxxxx.tar.bz2 file. You cando the following in one step, but it's really two steps, so
I will do this in two steps.
1. Uncompress the bzip2 file.
You can either do bunzip2 xxxxxx.tar.bz2 or bzip -d xxxxxx.tar.bz2
Both methods do exactly the same thing, slightly fewer character to type in 2nd method.
But the file is still tarr'd (tape archive). Now you have a file called xxxxxxx.tar
2. Un-archive the tar file.
tar xvf xxxxx.tar
Now usually ( but not always ) this will make a new directory, with all your files in it.
But I have found over the years, sometimes the files aren't in a directory, so when you un-archive it,
it clutters up the directory you are with a lot of new files, and it's sometimes difficult to tell
which files belong to which application. So I usually make a new directory and untar everything there
just in case.
Some file explorer GUI's such as MATE caja, will let you click on compressed/archived files
and let you look "inside" them. Usually if you right-click on the file, there is an option to "extract here".
Note: All distro's do not install bzip2 by default.