Low-Effort, Repeatable Post-Install Shell Setup, on Linux (USB-First)

Linux was Installed, like Kubuntu 24.04.3 ,
Looking for ease (low-effort)
repeatable way to run shell scripts
(a.sh, b.sh, c.sh, etc.)

one example:
after Linux install and
after copying files from USB to local disk and
after new PATH declared …

1st try to run a.sh from a USB stick or
if the USB stick is not present then, Local fallback,

Local fallback:
run a.sh locally, and

wanting this easy process to
scale to multiple machines.

suggest dir. name on usb
suggest Location on local linux disk to store a.sh …

example a.sh

clear  
ls -1v -w9 -plxhSs --format=single-column --group-directories-first --color=auto  
cmd1=` ls -qp | grep -c / `  
cmd2=` ls -qp | grep -vc / `  
cmd3=` ls -1qi  | grep -o '^ *[0-9]*' | wc -l `  
tput sgr0 ; tput setaf 4 ; pwd | tr 'n' '00'  
tput sgr0 ; tput setaf 4 ; echo "/"  
tput sgr0  
printf "%10d%s" $cmd1 ' Dirs       '   $cmd2 ' reg.files       '   $cmd3  ' files current Directory'  
echo " "

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