Can I choose a seat on a train ticket? The elderly travel and want to choose the lower berth

The train tickets bought online are all random. If you want to choose a seat, you need to buy a ticket at the train ticket agency.

No, online ticket purchase, whether it is Ctrip or 12306, the purchase of sleeper berths is random and cannot be selected. <br/>But I remember that the 12306 website once issued a notice that when the capacity is sufficient, the elderly over 60 years old who buy tickets online will automatically be assigned lower berths first.