EK Bard Sorcerer warlock gaining spells

[Whit]

Can someone explain how certain classes get spells.

We know cleric Druids pray for spells they need
Wizards arcane trickster have spellbooks that they memorize from

But how does EK get spells. Spell book? Just pop up in his mind or taught ? He can only learn abj evok and memorize. But he can change spells per level raise. So does he use a spell book to choose from or what?

Same with sorcerer warlock.

[ImproperJustice]

I figure the EK works like the bard or Ranger and studies a few spells until he knows how to cast them from memory.
I like to imagine that it is similar to a military drill or kata for them.

Sorcerers just “know” their magic.
Like Elsa, she just does stuff and magic happens.