Your fretting hand is what makes contact with the strings and holds down your notes and chords so it is crucial you know the best way to do this to get a clear sound from the guitar.
There are a few things we need to get right otherwise strings will be muted, buzz or won't ring clearly.
Mainly
Press down on the strings with the tip (pad) of your fingers.
Keep an arch/curve in your fingers.
Place your fingers as close to the front to the fret as possible (most important)
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