cd my/installation/dir
/<PATH_TO>/octeract-engine-X.X.X-Linux.sh
If in doubt about what to choose, go with automatic configuration.
If you went for auto you will need to log out and back in to reload the shell variables, or manually refresh them by running
source ~/.profile
for bash shells,
source ~/.zprofile
for zsh shells, and so on.
If you don’t know what that is, you are most likely running a bash shell. Also keep in mind that if you use source, it will only update the variables in the terminal where you typed it, and all future terminals that you open, but not in terminals you have already opened.
The automatic configuration will add the engine to your PATH, so after sourcing the .profile (or logging out and back in), you will be able to invoke it from a terminal like so:
octeract-engine --help