Took the US coalition 9 months to take Mosul using 122k soldiers, 24/7 USAF air support and UK and US special forces on the ground against just 11,000 enemy fighters(half of which were aged under 15). Those 122k were all trained by the US and UK and used American weapons and vehicles.
The allies destroyed 70% of the city and killed 12,000-40,000 civilians in the process, they stopped counting the Iraqi casualties about 20 days into it for morale reasons. They are still pulling bodies out of the rubble today as reconstruction is well underway 5 years later.
I'd like to remind you, no western nation has faced the weapons the Russians are facing(look how NATO "war veterans" fled in terror after Russia hit the foreign bases killing around 1400 volunteers earlier this month. The western nations haven't faced a real war in many decades.
Iraq and Afghanistan do not count in the slightest, not even close. A meme low level insurgency against goat herders and poppy farmers is not the same as a de facto NATO army with constant training,8 years of preparations, 24/7 intelligence support and daily resupplies from 20+ nations across 5 border zones.
This is a full blown conventional war