#1
Hello So far I was just learning songs like Master of Puppets,Harvester of Sorrow,Fear of the Dark,etc

So I want to learn how to improvise in songs
what scales should I play if the music starts in C chord,D chord,E chord,F chord,G chord, A chord , and B chord
Plz help me on this
#2
To improvise it would help to know the key signature of the song your playing. For Example, If its in F major, you would want to use the F Major Scale(or F Maj. Pentatonic) or the D Minor Scale(or D Minor Pentatonic). You could also use the D Blues scale to Solo/improvise.

However it all revolves around finding the key of the song. I believe theres a spot in the lessons section on the circle of fifths. That will help you find the key to a song. Also improvising would require knowledge of the scales listed/used, so that you know what notes would sound best.
#4
Yes. Know the musical alphabet:
C-C#-D-D#-E-F-F#-G-G#-A-A#-B.
Know that a tone = two (e.g. from C to D)
Know that semitone = one (e.g. C to C#)

Formula for the C Major Scale (a.ka. C Ionian):
Tone-tone-semitone-tone-tone-tone-semitone (referring to the distance between each note, starting from the first to second)

C-D-E-F-G-A-B-C
D-E-F#-G-A-B-C#-D
etc.
#5
And learn the modes. These are each note of the major scale played as a root moving up the neck.
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