May i know how to get to guangzhou west railway station from Guangzhou Baiyun international airport?

First I would like to know how to get to guangzhou west railway station from Guangzhou baiyun international airport.

Then I would like to book a second class of high speed train from Guangzhou west to Guilin west station on 12hb Feb 2020. Does the given seat, can fit my 24 inch luggage. May i know if my luggage is acceptable or not.

Lastly, I would like to know if I had exceed the luggage size/ weight how can I solve it?

Thank you.