Short answers, pulled from the story.
The modern State Duma was established by the Constitution of the Russian Federation in 1993, following the Russian constitutional crisis of that year. The earlier State Duma of the Russian Empire was founded in 1905 after the violence of the Russian Revolution of 1905.
The State Duma is the lower house of the Federal Assembly of Russia, paired with the Federation Council as the upper chamber. It consents to the appointment of the Prime Minister, can pass votes of no confidence in the government, appoints the Chairman of the Central Bank, and can bring impeachment charges against the President by a two-thirds majority.
Since the 2011 elections, the term length is 5 years. Before that it was 4 years from the 1999-2007 period, and the first Duma elected in 1993 served only 2 years.
Vyacheslav Volodin has served as Chairman of the State Duma since 2016. Previous chairmen include Sergey Naryshkin (2011-2016), Boris Gryzlov (2003-2011), Gennadiy Seleznyov (1996-2003), and Ivan Rybkin (1994-1996).
A 2016 exposé by Dissernet found that one in nine members of the State Duma had obtained academic degrees with theses that were substantially plagiarized and likely ghostwritten.
Any citizen of the Russian Federation aged 21 or older who has the right to participate in elections may be elected as a deputy to the State Duma. Deputies cannot simultaneously serve in the Federation Council, cannot hold other representative offices, and cannot work in the civil service; outside income is limited to teaching, research, or creative activities.