React component extensions for multi countries

I would like to create Contact Us form for multi countries, each countries form may have one or two additional or less fields in the form, but most of the fields are same. When I make change for Country A it shouldn't impact Country B, also Country B related changes shouldn't be there in the bundle of Country A. Both country form should have different configs, when I make country specific changes I should run the test only for specific country considering other country form shouldn't have any impact. What would be the best approach in react for country extension.

Your different thoughts would be help to pick the best approach thanks in advance