Open a terminal window.
Change directory in the terminal to docroot/themes/contrib/vartheme_bs5/scripts in the project.
docroot/themes/contrib/vartheme_bs5/scripts
Run the bash ./install-needed-tools.sh
bash ./install-needed-tools.sh
Follow with the list of instructions.
cd PROJECT_DIR_NAME/docroot/themes/contrib/vartheme_bs5/scripts bash ./install-needed-tools.sh