Tail wheel lock of Bf 110 C

[Redroach]

The possibility to keybind the tail-wheel lock was described as more or less a continuity thing with respect to Il-2 1946 - actually, I'm not sure if it works in any of CoD's planes.
Regarding taking off: Well, you must rely mostly on your rudder, perhaps peppered with left/right wheelbrakes (if you have single ones) and/or asymetric engine thrust (if you fly a multi-engine aircraft).
Mostly, you're left with just the rudder, but don't worry, you'll get the hang of it pretty quickly. Just react to your "swimming" with bold rudder input, and ease off when you're picking up speed and rudder effectiveness increases.