Ubuntu 20.04 post install BASH script

I currently have two post install scripts that work but need the functionality of both to be merged into one script The script must be able to display a menu that drills into other menus, and once the user has selected the category, then display a list of applications to install. The user must be able to select all the apps in that list that he wants to install, and then click a button to install all of them (as seen in [login to view URL]). A timer should run which indicates how long it took to perform the installation of each of the selected apps which is displayed to the user (time for each app and a total time) when he returns to his terminal (average internet speed during install period should also be displayed). Each app installation has its own script that needs to be called as a function from that main script. (as seen in the internet_original file).