Barre chords hurt? Two fixes I give every student who's stuck
My barre chords drove my own guitar teacher insane, so I know the struggle. The first fix: roll your index finger slightly onto its bony side — it presses the strings more evenly than the soft middle of the finger. The second: don't squeeze with your thumb, let the weight of your arm pull the barre in. And it's fine to place the barre first or the rest of the chord first, whatever works for your hand. Barre chords take time for everyone, so go at your own pace.