Edit Phone Input Field With Country Codes Dropdown

We would like to have a custom UI and behavior for phone number input field in registration/signin/checkout pages or any page that has a phone number.

We would like to have a dropdown of the country flags along with the country codes which the customer and choose his country code, then let him input a phone number in a field next to the flag.

Something like the image attached:

[attachment=15484:rerf.JPG]

it's from this addon: https://marketplace.cs-cart.com/proverka-i-standartizaciya-telefona-v-stile-google.html?sl=en&_ga=2.200267374.1510822684.1654700426-1689419891.1605779678

However, this add-on does not have all the functionality we need, which is why we want to create our custom one.

Any comments will help,

Thanks in advance!

rerf.JPG