How to parse cli args in a bash script

bash-args.sh

# https://www.baeldung.com/linux/use-command-line-arguments-in-bash-script
# usage: <script> -u <username> -a <age> -f <fullname>
while getopts u:a:f: flag
do
    case "${flag}" in
        u) username=${OPTARG};;
        a) age=${OPTARG};;
        f) fullname=${OPTARG};;
    esac
done
echo "Username: $username";
echo "Age: $age";
echo "Full Name: $fullname";