I’m flying into Delhi on Friday, the barcode is on my Air India e-ticket attached by email.
i didn’t book the flights, a TA did but forwarded the email on to me, I assume other airlines will need to do the same.
Our TA has told us to have a printed copy to facilitate entry into the airport on our return, we connect at Delhi for a domestic flight to Leh, no idea if it’s needed there or not, will report back Saturday.
The at times randomness of allocating board7ng passes does get tedious, I have boarding passes for both outbound flights, however I can only add the domestic one to wallet, the LHR to Delhi one doesn’t work, I’m sure I can get a paper one at check-in.