No, a printed copy is not necessary. You can just take a screenshot of the tickets in your mail or the confirmation SMS and show that to the on-ground team at the registration desk at the event
Sure you can, the ticket price for onspot entry is Rs. 699 per person. Just keep in mind, the tickets might be sold out before the event & in that case, there will be no ticket sales during event at the venue
No, all pets are welcome without any age restriction. Although, it's best to consult with your Vet about the suitability of getting your pet to a mass event before planning the trip, as your Vet and you would understand your pet's requirements best.