Button Box/USB Keyboard for PS4

Hi everybody,

as the title states I'm planning on building a button box/usb keyboard with about 30 buttons for my PS4, and since this is my first post u guys can figure out that I have not really the experience with Arduino.
So some advice would be highly appreciated.
I want to use this usb keyboard most of the time for my sim racing games. So here is what I already ordered:

A Arduino Leonardo, some wires and a enclosure big enough to handle hopefully most of the parts.

What I want the "keyboard" to do:

I want some keys to trigger a "character", but also at the same time a LED (just like if you press NumLock or Shift hold). This I would like to have with 3 keys.
The next thing I "need" is a trigger for the Pit limiter, which should be flashing if the button is pressed the first time and stop flashing if pressed the second time.
And on top of all I need a trigger for 2 more LEDs which should blink for a certain time after the button is pressed (let's say 10 second then stop).

And If that weren't more than enough to make my brain go crazy, I also want to use a analog stick as a "button", which doesn't need the functions: left-up, right-up, left-down and right-down. I really just need left, right, up and down (but if it's possible I wouldn't mind the push button function of an PS4 controller).

I was also thinking about a handbrake and shift knob which could be added through the box if needed. So I would need 2 sockets to plug in these. One would need just one key (handbrake) and the other needs of course 2 buttons for up and down shift.

Do you guys think that this is achievable with the board I ordered, from what I already researched I should be fine, but as I said before absolutely no clue where to start nore how to wire the whole thing up. As for the normally open buttons I might already know how to, since there are tons of examples around, but still I'm not 100% sure and really don't want to fuck up something.
Thanks in advance for any kind of help

Do you guys think that this is achievable with the board I ordered,

Yes the board can insert any key press or combinations of key presses you like into the keyboard buffer.

but as I said before absolutely no clue where to start nor how to wire the whole thing up

Start off simple, look at the examples in the HID libiary https://www.arduino.cc/en/Reference.MouseKeyboard

Build it up slowly one function at a time.