Seriously, your running before you can walk.
You must learn the basics before going complicated.
Forget leaders, lead core, pop ups.
Get a float rod, learn that. Plumbing the depth and then where to fish in the swim and why. Then progress to ledgering.
Then move onto carp and all its technicalities.
No offence, but is inexperienced people like you that tie a choddy wrong which leaves a fish tethered Until it dies