Hey, Rumble! Welcome to the community!

For (3), if you're running a windows PC, you can find the inputUserMappings file in C:\Program Files (x86)\Steam\steamapps\common\Cyberpunk 2077\r6\config. That's the one you're going to want to edit.

As a new speedrunner, the best advice I can give is record and post a full run of your chosen category, and don't worry about comparing yourself to other runners at this point. It doesn't matter how many times you die, or how many tricks you mess up. It doesn't even matter if you're using tricks at all. Just get something on the board that you can use as a gage to see what you need to work on. The sense of "Okay, I've finished a run. I can do better," is really important if you want to stick it out and improve. Once you have a run on the board, then you can start comparing to see what people are doing differently and make your own choices about how you want to change.

As a new Cyberpunk runner, you're smart to start with title. It's about 1/3rd the time as any% and you can practice all of the basic techniques used throughout both runs. Once you've got the basics down, you can branch out into any% or the miscellaneous runs.

Like DreK mentioned, the discord is where most of the magic happens in this community, so feel free to join in. Looking forward to seeing your name on the board!