Getting to Iran is the easy bit. The challenge may be the Iran-Pakistan border. There's a freight train these days but I'm not sure if there's a passenger service
https://www.seat61.com/europe-to-india-overland.htm...
Never say never, but my overland from Europe to South Africa looks less likely as years tick by. Maybe once I've finished renovating my house in 202* it could happen. Maybe. Likewise, an overland to Asia.