Select From Dropdown. Enter data and save result

I have 2 tables. Country and County (State).

What I want to do is Select a Country from a dropdown and then in another input field add a new County that belongs to that Country.

On saving the data I want the database to recognise that the County just added is related to the Country I selected.

Eg: Select England from the Country dropdown. Input Lancashire and the data saves.

So I end up with multiple County related to one Country.

Could some one point me to the answer please.

Thanks
Al.

Your DB should be like here:

Where the country should contain // list of states //

Use custom states to relate created states to the specific country