My tenant has a month to month lease here in va. How many days notice am I required to give for a lease termination and do those days start from the date of notification or the first day of the next full month?

What is the terms of the lease, it should be specific in a written lease.

If they are on a vebal month to month rental, they would get a 30 day notice. But with a written lease all of this is normally very specific.

Customary is a 30 day notice on a month to month lease ( rental)

If you are evicting them for non payment the rules of eviction are different