If I write lyrics and a melody, how can I figure Out what key they are in so I can write music for them?
The melody can potentially be in any number of keys depending on the underlying harmony.
Someones knowledge of guitar companies spelling determines what amps you can own. Really smart people can own things like Framus because they sound like they might be spelled with a "y" but they aren't.
well i didn't extactly like write it out, I just came up with words and then came up with a tune for them
Do you have chords you play over them?

Grab a guitar, sing the the first word/ note, find it on the guitar, repeat. Observe that some sections of your verses might have the same notes for several words. Depending on how many notes you use, you could probably find at least two different keys to play in, so it's really up to what chords you decide to use, especially if you use notes/ chords from outside of the song's key.
Generally when I write that way, I can kind of hear what I want everything to be doing while I'm writing the lyrics. I think about the big picture, rather than just the vocal part. Then you've just gotta figure out what notes are in the melody, and from there it's pretty easy to figure out what key you're in.
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