can't open laptop

What to do before you sell, give away, trade in, or recycle your Mac - Apple Support

You’ll want to read that, but will be starting at step 6 and erasing, and will be signing out of iCloud remotely via https://AppleID.Apple.Com

if this is not the login password forgotten but rather a firmware password, then you will need help from Apple: Set a firmware password on your Mac - Apple Support

Mike Macintosh Said:

"can't open laptop: [...]I do not not remember my passwords or code to open them.[...]"

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Reset the Forgotten Mac Password:

A. Where to Reset it:

Reset it using the login screen. You'd go through your Apple ID to perform this. Find out more here: If you Forgot your Mac Login Password - Apple Support. Make sure that caps lock is not enabled when typing it.

B. Troubleshooting the Reset:

Go here, if having issues: If you can't Reset your Mac Login Password - Apple Support

C. Learn from This:

Important: Keep a handwritten, hardcopy list of your passwords. Store it in a secret location that only you are knowledgeable of, and only you have access to. And, on top of that, don't share you passwords with anyone whomsoever.

Mike macintosh wrote:

but, I cannot one them up to clear them.

There are two passwords that can be forgotten here.

There is the login password, or the firmware password.

If the login password is what was forgotten, then erase the install.

Follow the list at the previously-linked list, starting at step 6.

You told us you’re selling it, so you will want to erase it anyway.

If this is the firmware password forgotten, then you will need to ask for help from Apple.

This is what you need to do before trading in your Macs: What to do before you sell, give away, trade in, or recycle your Mac - Apple Support