Running 2 website from single virtual host


Client having 2 websites like

and ( subdomain )

Codes and all files are the same. It will auto-detect language or base on user preference it shows language.
How to do it as an admin panel is one, the database is one.

Please help.?
Please correct me if I am wrong.

1 - Both domain hosted and working perfectly
2 - Change in sub-domaian virtual host - Document Root to main domain ( so that both will take same files )
3 - As both having SSL so need to have diff virtual host ( ?????????????? )

Map to same virtual host ?? Will Virtual Host Root and Config File also point to same ??

Please guide