Beauvais to Esbly
Can I get a train from Paris Beauvais to the Esbly train station?
Yes, you can take the train from Beauvais to Esbly. It entrails lots of transfers as you have to go into Paris. If you took the train from Beauvais, you'd go Beauvais to Gare du Nord to Gare de l'Est to Esbly. I don't think you can buy one ticket as you'll change train systems and need to take the Paris metro from Gare du Nord to Gare de l'Est. You could also walk as Gare du Nord isn't far from Gare de l'Est.
Another suggestion is to take the Paris shuttle from the airport into Paris and from Porte Maillot, where the shuttle arrives take the metro to Gare de l'Est. This might be esaiest as then you don't have to hassle with getting from the airport to the Beauvais train station.
Either way you'll take the Transilien line P from Gare de l'Est to Esbly. I'd put travel time down to about 2.5 hours.