Invoke Future Method From Process Builder

Sample Code:

public class ContactProcessBuilderHandler {
    
    @InvocableMethod 
    public static void sendNotification(List<String> contactIds) {
        sendEmailToContacts(contactIds);
    }
    
    @future //Use callout = true, for callouts
    public static void sendEmailToContacts(List<String> contactIds) {
        //Write your business logic
    }
}