Indore to Prayagraj bus

Hi guys, Can you please let me know where to find nearest bus stand to indore airport. We wish to travel from indore to Prayagraj by bus. We appreciate if we can sleeper government bus. If not private bus is also fine. We don't wish to book online given the no. of raising frauds. We wish to go to bus stand, see the bus and book there directly. Please guide us. Thanks in advance