I'm still fairly new to tanks and I'm really curious about three specific Soviet tanks of WW2.

The tanks are the T-34/85, the KV-2, and the IS-2.

I'm not asking which one is the best. I'm curious about the driving mechanisms, reload process, performance, and so forth.

If someone with higher experience than me could answer, that'd be nice.

7663039
You might find some decent info on youtube, a professional military historian did a series called Inside the Chieftains Hatch, here's part one of the T34
(81) Inside the Chieftain's Hatch: T-34-85, Episode 1 - YouTube
Hope it helps :)
Things to say about the KV-2 and the IS-2. Not much, the KV series was notorious for being a pig to drive. Clutch was solid as rock and the gear box needed a hammer to change gears at times, plus it was grossly underpowered, altogether making it a bit of a basket case mechanically. Also the sheer size and poor weight distribution of the turret on the KV2 meant it could only rotate when the vehicle was more or less level. Extremely well armoured for an early war tank though. Broad tracks meant it handled unpleasant terrain surprisingly well, or at least better than German tanks. Overall crews were split on whether to love or hate it.
The only things that really stand out in my mind about the IS2 were the excellent frontal armour, could protect it from the infamous 88 deathray. had excellent mobility for a vehicle of it's size and weight. The Soviets had figured out most of the reliability issues, so it was fairly rugged. On the down side, the size of the main gun made the turret quite cramped and awkward to work in, plus the shell and charge had to be loaded separately, meaning it had a very low rate of fire.
If memory serves, all three used clutch and break steering mechanisms.
Another good source of info would be Tank Encyclopedia, the first online tank museum (tanks-encyclopedia.com)

7663039
You mentioned 3 things, so I'm going to cover those only concerning T-34/85, which I am most familiar with.

Driving mechanisms.

T-34/85 used a clutch and brake mechanism for steering, which is about as basic as you can get when it comes to tank steering methods. The way this works is dead simple. You have two tillers. They default to a forward position, and in this position the tracks get power when you push on the accelerator. Pull one back a little and it will disengage the clutch, cutting power to that track. The tank will start to turn in the direction of the track with the cut power as it slows down due to friction. The worse the terrain the quicker this happens. In mud for example, the unpowered track will slow down pretty quick. Pull the tiller back further and the brakes come on. With this system it is not possible for the tank to turn in place, as that requires the ability to run one track forward and one in reverse at the same time.
The transmission is a 5 speed, and more or less works without too much effort. The 76s used a 4 speed for most of their lifes that was pretty horrid.

I'll edit in the other answers later

7663039
Both T-34 and KV-1 tanks used clutch brake steering, and similar transmissions IIRC. IS-2 used epicyclic steering, basically at the end of each drive axle there is a two-speed gear. Downshift one gear to slow the track, and the tank turns.