Internal Monologue pertaining to tonality

[Easemaker]

Getting back into music and trying to decide the best approach to my inner monologue, or the voice inside your head.

My main question is: As you read sheet music or play should you be saying the notes in your head (the words G sharp or A flat) or hear the tone of G#?

Saying the words A B C ect along with playing the tone work fine for me but when saying A sharp C sharp this takes longer(being two words) and seems unnecessairly cumbersome.

I never understood why the notes were not labeled A-L. Is this because of the physical wave pattern of harmonics?

Also having a hard time assigning flats and sharps to notes on the staff according to the key signature. This also seems unnecessarily complicated to my noob self. Why the extra step? Do you have any tips or lessons handy that could help me with this? My guess is this just takes a lot of hard work and time.

Thank you for reading this and any information you provide.