Joy,

What you want to learn is 1. be able to write down your tunes.
You need to know your sharps and flats for basic scales. In the meantime you can use the key of C which has no sharps or flats.
2. You need to know time signatures and how to read rhythm.
3. You need to know how to transpose. The best way is to start with chords. Use roman numerals to designate the chords in a song. ie: C major would be I major. F major would be 1V major (based on the fourth note of the C scale) Use three chord songs to practice this. Once you identify the chords in a song with numerals, then transpose it to as many keys as you can. This means you will have to know more scales than the Key of C.
4. Learn to sight-sing music. The best way to do this is to take a melody line and write the position of the note underneath the note on the staff using arabic numbers. Ie:
suppose the notes are C,E,G,F,E,D,C you would write (if you are in the key of C) 1,3,5,4,3,2,1. Practice this exercise in the key of C before going on to sharps and flats. Feel free to post any questions to me on Mudcat.

Sincerely

Frank