Undoing a commit in git

When forgot something on a commit:

git reset –soft HEAD^ — move to the commit one before the HEAD.

undo the last commit and move everything from that commit back into staging.

git commit –amend -m « modify something and add it to the last commit »

git reset –hard HEAD^ -undo last commit and all changes

git reset –hard HEAD^^ – undo last two commits and all changes