Short answers, pulled from the story.
The Silesian offensives were two Soviet Red Army operations conducted in Silesia in early 1945 against the German Wehrmacht on the Eastern Front. The Lower Silesian offensive ran from the 8th to the 24th of February 1945, and the Upper Silesian offensive ran from the 15th to the 31st of March. Their primary purpose was to protect the flanks of the Soviet advance on Berlin.
The 1st Ukrainian Front, under the command of Ivan Konev, carried out the Silesian offensives. Konev's forces had previously completed the Vistula-Oder offensive before being directed westward into Silesia.
According to Soviet information, the Germans lost 54,000 soldiers in the Upper Silesian offensive: 40,000 killed and 14,000 captured.
Securing the flanks of the Soviet advance was deemed necessary before the main assault on Berlin could proceed. The flank-protection operations pushed the final Berlin offensive from its original February target date to April, a delay of approximately two months.
Stalin's decision to delay the Berlin push from February to April 1945 has been disputed. Some historians argue a February attack could have ended the war faster with fewer casualties; others cite the risk of German counterattack from remnants of the Czech fortification system. Stalin's delay also allowed Soviet forces to occupy substantial parts of Austria in the Vienna offensive, a likely political motivation.
By mid-April 1945, the East Pomeranian offensive had reached Stettin, an important German port city now known as Szczecin.