Take the Huyue Express Bus for example, from Beijing to Shenyang, takes 8 hours on the way and 145yuan per adult.
Shengyang is far from Shanghai, over 2,000 kilometers. So, it is suggested that you fly to Shanghai from Shenyang. You may check the real-time flight ticket at China Flights(https://www.travelchinaguide.com/china-flights/)