Conditional fields

Hi,
I have been able to add custom fields to my orders by adding them to the snipcart-templates.html and this works great. However, I would like one of them to be conditional.

Specifically, when the customer enters a billing address that is located in Europe, I would like to enable a new field to capture their VAT number. At the moment, this field is not conditional and is shown to customers of all locations.

We have another purpose for conditional fields, but this one is a bit more complicated. We would like to have a checkbox that asks if the customer would like to ship on their own FedEx account. If they tick this checkbox, we would like to enable a field to capture their account number. ALSO, in this case we would need to set the shipping charge to zero, as the shipping would be charged to the given account number.

Can you please help me to do this? I am not familiar with Vue JS, but I’m willing to learn a bit if necessary.

Jeff