I suck it so much as I can see no wonder why I immediately hated it as child when first time downloaded it

Everyone sucked when they just started

Yeah, but small me had to be good at everything and if I was not good at something then the thing was rigged according to my thinking.

Well my ADHD wants me to be good at everything now
This is why i didn't quit geometry dash

Understandable, by the way does holding make the cube jump more higher or is it just a feeling that my cube is jumping higher?

Yeah if you hold the second jump will be higher
But the third and all of the later will be same height as 2nd

And also, who is to blame when I tap on screen but I am not jumping?
A: my device
B: game's psychics
C: not my skills?

(specificly when on edge of block)

If you're on the edge of a block then it's device/game
If you're on a phone and you have 60 fps the game can only detect if you're tapping on the screen 60 times per second