North Station or Panjin Station?

Oh, you are suggested to take a train from Beijing Railway Station to PJ Railway Station. This railway station is nearer to the red beach scenic area.
PJ Railway Station is located at near to North Shuangxing Road, Shuangzitai District.
And the north railway station is located at no. 379, Sun Village, Tianshui County.

From the railway station, take a taxi to Zuanjing Gymnasium or Jinjiang Hotel. There are direct buses to the Red Beach. It will take 40 to 50 mins on the way. And the operating hours are from 07:00 to 17:00. If you take a taxi to the beach directly, the fare is CNY120 or a little higher.

About the hotel, what's your budget about your accomdation?
You can go to Jinjiang Inn (PJ Railway Station Branch). Just walk to this hotel from the station directly. It has comfortable living environment. The fare is CNY 100 to 200 per night. This hotel is located at the south side of the railway station (the opposite of the bus station). You can easily find it.

I'm a local. As for me, Panjin Station is nearer and more convenient. Actually I suggest you search a travel agency going to Red Beach. There are not any bus stations in the Red Beach area.