Difference between IDs

Hello everyone!

I’m trying to get a better understanding on how IDs work.

Let’s say I started creating my principal for the NNS using Internet Identity

First I get an “Identity Anchor”
Also a seed a phrase with 24 words

Entering the NNS, I get a “Main” which is the public “Address”
Then if I go to canisters I can get my “Principal ID”

So far so good!

But then if I try to import the seed phrase to ther wallets like Plug or Stoic, It can only be a 12 word instead of the 24 I got from Internet Identity

Now Stoic let’s me login using Internet Identity and surprise, I can’t find my Main or my Principal ID in which I was using the NNS

Also when I try to get the identity.pem using keysmith and my 24 seed I get another completly different address and principal ID

I would just like to know what in the world is going on

Please advice