Train 18 - तेरी प्यारी प्यारी Livery को किसी की नज़र न लगे

i want to travel from Vijayawada to New delhi by 12621 Tamil Nadu express. As i am travelling with my dog, i want 4 first AC seats which is not available from vijayawada, can i book my tickets from chennai central to new delhi and provide boarding point as vijayawada through online irctc booking? if yes, then how to book pet from vijayawada..

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