Sellering studied law and has lived in Mecklenburg-Vorpommern since 1994, where he worked at the courts of Schwerin and Greifswald.

He is also a member of the German-Russian Friendship Group set up by the German Bundesrat and the Russian Federation Council.

He had campaigned on local issues, urging voters to focus on jobs creation in the wind turbine sector, decentralized integration of refugees and pension parity with Germany's western regions.

On 30 May 2017 Sellering announced his resignation from all official political positions after he had been diagnosed with lymph cancer that needed immediate treatment.

[1] From 2021 to 2022, Selling served as chairman of the Stiftung Klima- und Umweltschutz MV (Climate and Environment Protection Foundation), an entity set up by the government of Mecklenburg-Vorpommern in January 2021 and endowed with 20 million euros from Nord Stream 2 AG, a Switzerland-based company owned by Gazprom.