From the Instagram app:

1. Open the Instagram app.
2. Tap your profile icon in the bottom right corner.
3. Tap the three dots in the top right corner.
4. Tap Settings.
5. Scroll down and tap Account.
6. Tap Account ownership and control.
7. Tap Deactivation or deletion.
8. Tap Delete account.
9. Enter your password and tap Continue.
10. Tap Delete [username].

From a web browser:

1. Go to the Instagram Help Center: https://help.instagram.com/139886812848894
2. Click on Delete your account.
3. Log in to your account.
4. Select a reason why you want to delete your account.
5. Re-enter your password.
6. Click on Delete [username].

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