its very easy to change Instagram account password.
use different password if you want to change your Instagram account password. similar password will be difficult to change.
open your Instagram profile and go to setting like this
now select option "Change Password " like this
enter your current password on top line like this
now write your new password on 2nd top like and then re-enter your new password on bottom line again.
then click on top arrow sign to confirm your new password like this
your password changed.
thankyou....