The February Revolution resulted in a very complicated, very confusing period until the Bolshevik coup where both the Duma (the provisional government) and the Petrograd Soviet (which held support from huge swathes of the army and urban workers) shared power in Russia. Most of the time, the Socialist-Revolutionaries held the majority of power in the Soviet, and the Duma brought in more of the moderate socialists to give an air of legitimacy legitimacy popular control to their actions. The S-R also formed a coalition which included the Bolsheviks, among others, and these were widely popular.

However, the continued war in the west against Germany was growing incredibly unpopular and the leader of the provisional government, Kerensky, lost most of what remained of his support when the Russian offensive of 1917 was launched and failed. The October Revolution was a coup, the Bolsheviks (a small part of the Soviet) seeing the blood in the water and essentially giving supremacy of the government from the dual system to the Soviet. The Bolsheviks still wanted to prove their popularity, so the planned elections for the Constituent Assembly a few weeks later were allowed to go ahead. By this point, the coalition between the Bolsheviks and S-R was largely defunct.

On the 25th of November the Bolsheviks were delivered a shocking blow. Despite their massive support in the army and the urban industrial workers, the Socialist-Revolutionaries were able to mobilise enough votes in other blocs to take over one third of the vote, a further 10% by the Ukrainian Socialist Revolutionary party (an altogether similar group), and only 20-25% of votes taken by the Bolsheviks. The first free elections in Russia would be for nothing, as the Bolsheviks immediately barred entry to the Soviets to anyone but themselves and shortly after dissolved the Constituent Assembly in January, beginning the civil war.

I can't give anywhere near as detailed a narrative for Germany, but it was similar in that there were unified (largely centre-left to hard left wing) blocs which organised an ousting of the previous monarchy, but rather than form anything similar to Russia's dual system, they formed a parliament and explicitly worked to prevent a Bolshevik-style coup. The army, while extremely conservative, was given enough concessions by the new government that a common understanding developed, and when events like the Spartacist Uprising occured, they were crushed due to a lack of support from any major bloc.

So, put simply, the Russian Revolution and German Revolution had many similarities in that it was largely a coalition of left-leaning groups that formed the government, but diverged in that the extreme was able to seize power in Russia but failed to do so in Germany. This was due to the their respective armies being largely the opposite politically, conservative in Germany and Bolshevik in Russia, the German government having at least the minimum level of support from the army while the Russian government was eventually dissolved by the Bolsheviks without resistance.